Mercedes-Benz GLC-Class vs Audi RS Q3

What's the difference?

The GLC300 Coupe isn't quite as great when it comes to being a family car as the regular SUV version of the GLC, and that's purely down to the sloping roofline which not only makes access more difficult to the second row but reduces boot capacity.

That said, the GLC300 Coupe makes a much better family car than a Mercedes-Benz C-Class sedan, or any sedan.

Easy and enjoyable to drive, packed with great features and still practical, the GLC300 Coupe would still cut it as a good family car.

The Audi RS Q3 Sportback edition 10 years is dynamically brilliant, beautifully finished and surprisingly civilised on day-to-day duty. A polished compact performance package that even in this special 'get-it-while-you-can' guise offers compelling value relative to its direct competitors.

Coupe SUVs aren’t for everybody… they’re not even for lots of people. But the design of an SUV with its roof cut down so that it meets the tailgate at an almost sportscar-like angle appeals to more than a few fans. The thing is they don’t just like the look, they love it, and they also probably enjoy how much the styling makes other people cranky.

To my eyes the GLC300 Coupe is the best execution of the bodystyle compared to those of BMW and Audi. There’s an elegance to the GLC300 Coupe and the AMG-line adds a tough look that only enhances the solid, powerful but pretty look.

The GLC Coupe is a mid-sized SUV and this new generation model is a bit bigger the previous one and now measures 31mm longer at 4763mm end to end, it’s 1890mm wide, 1605mm tall and has a wheelbase of 2888mm.

It’s also more aerodynamic than ever. No seriously, it’s drag coefficient is now 0.27 and it looks like a bar of soap - and it's about as slippery as one, too.

More curved surfaces await inside with a dashboard that pours down into the large centre console and it's adorned with a sloping and large portrait-style media screen. 

At night or in tunnels the ambient lighting glows through the air vents and skirts the edges of the door trims, console and dashboard.

It’s a minimalist and high-tech cockpit with modern sports seats up front and a Nappa leather wrapped steering wheel with its twin blade design.  

So, how does the coupe design work for family practicality? Let’s take a look.

There's a lot going on with the RS Q3's exterior design; a mix of jagged lights, hard character lines, broad haunches and multiple vents surrounding the brand's signature, six-sided grille up front.

The big 21-inch rims fill the arches nicely and the rear features a deep diffuser with fat exhaust finishers poking out either side.

It's a purposeful, macho look and the Sportback edition 10 years is defined by a black package which adds gloss black to the side window trim, front spoiler blade, side blades, rear diffuser and exterior mirrors.

The limited edition is available in two colours, 'Chronos Grey metallic', which is unique to this model and 'Dew Silver matte' which will now be added to the broader RS Q3 colour palette.

Premium performance feels like the dominant theme inside with a typically Audi tech-focused approach including high-quality brushed metal elements, matt carbon inserts and quilted leather trim on the heavily bolstered front seats.

A meticulous attention to detail is obvious and the bottom line is it's all about the driver. A grippy, flat-bottom, leather-trimmed steering wheel looks as good as it feels, sleek screens enhance the racy vibe and the mix of physical and digital controls is sensible.

SUVs are the most practical cars for families because of the better access to the cabin thanks to their large doors and slightly elevated ride height, their big boots with wide and tall hatch openings and their high flat rooflines. They’re essentially raised station wagons.

A coupe-style SUV still has four doors but they are less boxy due to the sloping roofline which falls away quickly to meet the tailgate at a lower point. The effect is a sporty-looking shape but practicality is lost in this exercise of form over function.

The second row doorways aren’t as large as those on the regular SUV. I did a side-by-side test and felt like I had to duck under the sloping roof when getting out of the back seat.

The smaller opening also made it trickier to lift my toddler daughter into her baby seat.

The sidesteps are also surprisingly handy for bigger kids and my eight-year-old used them every time when climbing into the car.

Cabin storage is outstanding with huge door pockets and cupholders in both rows, and while the 545-litre boot in the GLC300 Coupe is 80 litres smaller than the cargo capacity of the regular GLC SUV, it's bigger than the previous version of the Coupe.

As for people space, there’s enough headroom for me at 189cm tall in the back seat and heaps of legroom, even behind my driving position.

I’ve mentioned the lack of climate control in the second row, but also should point out that there are no USB ports back there either.

There are USB ports in the big centre console box upfront and a long cord should be able to make it to the second row. 

There’s a wireless phone charger but it's housed in the bowels of the centre console too, and you’ll need to weave your hand while clasping the phone under the shiny black trapdoor, past the cupholders possibly with drinks in them and almost under the dashboard.

Snug but spacious enough, the RS Q3 Sportback's driver and front passenger are provided with plenty of breathing room without upsetting the intimate, performance car feel. Just be prepared for a bit of head-ducking physical origami when folding yourself into either of the heavily bolstered front seats.

Storage includes door bins with room for bottles, two generous cupholders in the centre console, a lidded tray in front of the gearshift (which doubles as the wireless device charging bay), a storage compartment and owners manual holder under the front seats, a modest glove box and an adjustable front centre armrest with storage compartment.

Given this car measures just over 4.5m end-to-end, a close to 2.7m wheelbase is significant  and rear room is generous given the Q3's overall footprint. Plenty of head and legroom (for me at 183cm) with enough width for three adults on short journeys. A trio of up to teenage kids will be fine.

The back seat is able to slide for extra legroom (and slightly less boot space), while backrest angle is also adjustable.

Storage runs to small bins in the doors, a fold-down centre armrest (with two pop-up cupholders) and storage nets on the back of the front seats. Directional and temperature control in the rear for the ventilation system is a big plus.

Power and connectivity options run to a 12V outlet and two USB sockets in the front (Type A and C), another two Type C sockets in the back and a second 12-volt jack in the boot.

Speaking of which, cargo volume with all seats up is a handy 530 litres, enough to swallow CarsGuide's three-piece luggage set or large pram (the latter with room to spare) and 1400 litres with the 40/20/40 split-folding rear seat lowered.

The loading lip is low, a stainless steel sill protector helps minimise scuffs and scratches and the hands-free power tailgate is welcome.

If you're keen to hook up the boat or horse float the RS Q3 is able to tow a braked trailer up to 1900kg (750kg unbraked), but don't bother looking for a spare of any description, a repair/inflator kit is your only option. Boo...

The Audi RS Q3 Sportback edition 10 years is priced at $102,900, before on-road costs, which is a $3800 premium over the standard issue version.

For those extra dollars the car is upgraded with specific 21-inch black alloy rims, black badging and brake calipers as well as (three-stage heated) 'RS' Nappa leather-trimmed sports front seats with contrast 'Copper Honeycomb' stitching.

The fancy stitching extends to the Alcantara-trimmed steering wheel and gear lever, the RS floor mats also feature copper highlights and the door downlighting projects a unique rhombus design.

At that money the RS Q3 lines up against BMW's firecracker X3 M40i ($126,800), the ferocious Mercedes-AMG GLA45 S ($121,900) with the Jaguar E-Pace 300 Sport AWD ($84,500) the only other similarly pitched compact performance SUV within $20K of the Audi.

And as well as the performance and safety tech covered later in the review, the RS Q3's standard features list includes, three-zone climate control, adaptive cruise control, keyless entry and start, Nappa leather trim, ambient lighting (with 30 colour choices), an RS sport contour leather-trimmed steering wheel, 12.3-inch digital instrument cluster, 10.1-inch multimedia display (with text and voice control), (wired) Android Auto and Apple CarPlay, sat nav and wireless device charging.

There's also a Bang & Olufsen '3D Sound System' (15-speaker with 680-watt, 16-channel amp), digital radio, 21-inch alloys, electronically-controlled adaptive dampers, auto Matrix LED headlights (with RS-specific darkened trim) and a hands-free power tailgate. And it's worth noting metallic and pearl effect paint finishes are offered at no extra cost.

Pretty impressive. Especially when you consider even this special edition RS Q3 is $20,000 cheaper than its primary BMW and Merc-AMG rivals.

The GLC300 Coupe has a 2.0-litre four-cylinder turbo-petrol engine making 190kW of power and 400Nm of torque.

There’s also an overboost function which allows the engine to make an extra 17kW and 200Nm just for a brief moment, but that extra dollop of grunt combined with the regular output provides impressive acceleration (0-100km/h in about 6.3 seconds) for overtaking or moving quickly when you need to.

A smooth nine-speed automatic transmission sends the drive to all-four wheels.

The GLC300 Coupe is all-wheel drive and while there’s a setting for rougher terrain, along with one for comfort, eco and sport, but I’d make sure that it doesn’t get any more adventurous than tame gravel and dirt roads.

Mercedes-Benz refers to the GLC300 Coupe as a mild hybrid and this is because it has a 48-volt system and an integrated starter-generator.

This type of hybrid doesn’t use electric motors, doesn’t drive the wheels and won’t save much fuel, but it will provide efficiencies by supporting the engine and when coasting, plus will reduce petrol consumption to a small degree.

The RS Q3 Sportback is powered by a 2.5-litre in-line five-cylinder intercooled turbo-petrol engine sending drive to all four wheels via a seven-speed dual-clutch automatic transmission and Audi's quattro permanent all-wheel drive system based on an electronically-controlled multi-plate clutch pack.

Featuring a cast iron block, alloy head, direct-injection as well as variable intake and exhaust cam adjustment, the (EA855) engine features a special firing order (1-2-4-5-3), the odd number of cylinders producing a signature engine sound and exhaust note reminiscent of the 1980s 'Ur' Quattro.

Peak power is 294kW from 5850-7000rpm and maximum torque is 480Nm delivered across a broad plateau from 1950-5850rpm.

As we mentioned above the GLC300 Coupe's 48-volt mild hybrid system is not the kind of hybrid that will allow you to drive miles on electric power, nor will it dramatically reduce fuel consumption in the way a parallel, series or plug-in hybrid will. But every bit of efficiency helps.

Mercedes-Benz says the GLC300 Coupe will use 7.7L/100km after a combination of open and urban roads. 

We had the GLC300 Coupe for just two days, but in that time my family covered 176km of regular daily usage which took in motorways but mainly suburban duties such as the school run, supermarket dashes, that sort of thing.

In our fuel test we measured 14.48 litres at the fuel pump which works out to be an on-test fuel use figure of 8.2L/100km and not far off the manufacturer’s claim. 

While this fuel consumption isn’t overly high, a plug-in hybrid or even a parallel or series hybrid could return about 5.0L/100km or less.

Mercedes-Benz has dropped plug-in hybrids from its Australian range which is a shame because it would be good to see more efficient options in the GLC range. Of course if you want more efficiency from a Benz of the same size, there is always the fully electric EQB or EQC.

Audi's official fuel economy number for the RS Q3 on the combined cycle is 8.9L/100km, the 2.5-litre turbo-petrol five-cylinder engine emitting 204g/km of CO2 in the process. Stop-start is standard.

We covered city, suburban and some freeway running on test, returning an (indicated) average of 9.6L/100km. And that's pretty good, given we pushed on enthusiastically on a reasonably regular basis.

The fuel tank requires 63 litres of 98 RON premium unleaded to fill it which translates to a theoretical range of just over 700km, shrinking to around 650km based on our real-world number.

There’s a lot to like here but the short version is the GLC300 Coupe has a comfortable ride, but good handling, with a responsive engine, although rear visibility through the small back window is poor.

If we drill down a bit further I can tell you that excellent cameras around the car will help you check to make sure kids aren’t running around behind you and that forward and side visibility through the window is good.

An important takeaway is that the GLC300 Coupe is easy to drive with light steering and an engine that’s mild and controlled in its power delivery.

The gear shifter is mounted on the steering column, in the same way an indicator lever is. So putting the car into Drive, Reverse and Park is so easy and means you don’t have to take your hands off the steering wheel. 

As a family car I liked the good body control and composed ride. We have a small toddler that we can sometimes only get to sleep by taking her for a drive and we found that she could nod off and not be woken by potholes and speed bumps or too much leaning in the corners. 

It still seems counterintuitive when a high-riding SUV is tuned to perform and handle like a low-slung sports car but here we are. And Audi executes this mystifying transformation as expertly as any carmaker in the automotive world.

Audi says the RS Q3 Sportback will blast from 0-100km/h in 4.5 seconds. Anything under 5.0 seconds is properly fast, and there's nothing quite like the deep-throated bellow of a VW Group in-line five to raise the hairs on the back of your neck.

The RS Q3's sport exhaust system is a dual-branch set-up with exhaust flap control, and people of a certain age will instantly imagine themselves matching it with Ari Vatanen, Walter Röhrl and Michèle Mouton on a suburban special stage behind the wheel of a 1980s Group B Sport Quattro rally car (actually, the school drop off at an infinitely more sensible pace).

The car weighs in at a not insubstantial 1775kg, but 480Nm, available all the way from 1950rpm to 5850rpm, means a near instant surge of fierce acceleration is always lurking under your right foot.

And the VW Group is on the pace when it comes to dual-clutch auto transmissions, from Porsche's 'PDK' and VW's 'DSG' to Lambo's 'DCT' and Audi's 'S tronic'.

The RS Q3's seven-speed unit is quick and positive, the wheel-mounted paddles ramping up the engagement factor.

The variable ratio, electrically-assisted steering is capital G Great. Well weighted and precise with reassuring road feel and the Alcantara trimmed wheel is a nice way to access it all.

Suspension is by struts at the front and multi-links (four) at the rear with adaptive dampers on-board.

Despite running on 21-inch rims, shod with high-performance 255/35 Continental PremiumContact 6 rubber, ride comfort is surprisingly good.

Dial in 'Comfort' mode via the 'Drive Select' system and the impact of even substantial bumps is softened off appreciably.

An ideal set-up would be the first 'RS1' short-cut Drive Select button set for Comfort suspension, with throttle, steering and transmission set to maximum attack and the second 'RS2' mode tweaking the suspension to track-day level, too.

Push on through your favourite set of bends and you can feel the electronic wheel-selective torque control system keeping everything under control. This car puts its power down through sweeping sections with fuss-free authority.

The RS-specific menu in the digital instrument cluster provides extra instrumentation in the shape of a power/torque display, G meter and lap timer. Fun!

The brakes are professional grade with big ventilated rotors all around and aluminium fixed calipers at the front.

But beware, the flip side of the RS Q3's quick steering response is a sizeable 11.8m turning circle. Take your time when parking.

Although the Audi Q3 received a maximum five-star ANCAP score in 2019, the RS Q3 was specifically excluded from the assessment, so it's officially untested.

But the car boasts an extensive active (crash-avoidance) safety suite including, auto emergency braking (AEB) (5.0km/h to 85km/h for pedestrians and cyclists and up to 250km/h for vehicles), adaptive cruise control (with stop-go function and active lane assist), lane change warning and lane departure warning (with lane keeping assist).

There's also 'Attention Assist' (warning tone and visual signal if the system determines the driver's attention may be lapsing), front and rear parking sensors, a reversing camera with 360-degree view, rear cross-traffic alert, tyre pressure monitoring, 'Hill hold assist' and hill descent control.

If, despite all that, a crash is unavoidable there are six airbags on-board (front and side for the driver and front passenger as well as full-length curtains). The RS Q3's showing its (10-year) age here because additional rear side and front centre bags are close to the norm now.

Nice to see a first aid kit and warning triangle included and there are three top tethers and two ISOFIX anchor points for securing baby capsules and child seats across the second row.

The GLC300 is covered by Mercedes-Benz's five-year, unlimited-kilometre warranty. 

Services are annually or every 25,000km. And you can buy a three-year service plan for about $3000.

Audi Australia covers all the models it sells with a five-year/unlimited km warranty with 24-hour roadside assistance included for the duration. Pretty much cost-of-entry in this part of the market.

Paintwork defects are also covered for five years, and the body is warranted against corrosion (to the point of perforation) for no less than 12 years. Nice.

Service intervals are 12 months/15,000km and capped-price servicing is available, a five-year/75,000km plan for the RS Q3 costing $3580, an annual average of $770. Fairly steep.

An 'Audi Advantage' package is also available, adding an extra two years' worth of warranty, scheduled servicing and roadside assistance (to the end of any existing term) for $3800.