BMW Alpina B5 vs BMW M5

What's the difference?

The Alpina B5 is a special car – more special than most people will ever give you credit for if you own one. Those that do know what an Alpina is will let you know; people will cross dangerously busy streets to talk to you about your car. Insanely fast, almost incomprehensibly comfortable and effortlessly powerful to drive.

Let’s get one thing out of the way: the new M5 is a very good car. Considering the emissions limitations and size increase of its base model, it is an impressive bit of engineering. 

What’s trickier is deciding whether the new car is really better to drive. Less edgy but supremely comfortable and quiet; BMW leaned into the daily usability of the plug-in hybrid M5 rather than amping the petrol-electric system for maximum thrills. And do you know what? That’s fine with me. 

The new M5 still performs on road and track and does an incredible job of hiding its weight (most of the time). Perhaps the G90 is a little more Audi RS6 than F90 in its demeanour but some would argue that’s no bad thing. 

The concept of the BMW M5 is not static, it evolves with the times, and the G90 is no exception. Expect future Competition and CS variants to unlock some extra lunacy. 

Note: CarsGuide attended this event as a guest of the manufacturer, with meals provided.

Interesting is the right word for it, because while it might be questionable that Alpina's changes to the exterior are aesthetic pleasing, they are definitely intriguing to those who aren't familiar with the brand.

First, there are those 20-spoke wheels. Alpinas have worn this style of wheel forever and they've become the most famous outward sign that this is not just another BMW. So don't under any circumstances take them off and replace them with anything else. You'd be run out of town by the Alpina mafia.

Yes, they're more painful to clean than a cheese grater (trust me, I know. And if you look closely at these images you can see the dirty bits I've missed), but if you really don't like them then perhaps it's a sign this car isn't for you.

Then there's the boot-lid spoiler. It's square and 1980s'-looking, it also appears a bit like it's been bought online and installed by a teenager, but again, this is another Alpina tradition and it suits the car's character perfectly.

All right, those pinstripes; they're known as the Deco-Set and are a hat-tip to the Alpina racecars of the 1970s and '80s. Again, don't take these off, your Alpina will drop through the centre of the Earth in value. These are also part-and-parcel of owning one of these cars. I'm not a massive fan of them.

But I'm all about that front spoiler, with the floating Alpina lettering that you can option in silver, high-gloss black or gold.

Inside, there are fewer Alpina additions, but they're nonetheless unmissable. There's the Alpina-badged steering wheel, and a new virtual instrument cluster, embossed headrests and  illuminated door sills.

There's also the little numbered plaque on the centre console which proves its authenticity, ours was number 49. Out of how many? I don't know. But I do know Alpina produces only about 1700 cars globally a year. Rolls Royce does about 4000. So, you can rest assured your B5 is exclusive.

At almost 5m long, 1.9m wide and 1.5m tall, the B5 is a large saloon, but having recently reviewed the Alpina B7 it feels small in comparison. How does it drive? We're getting there.

The M5’s raw size is what you notice first. The G90 M5 is a whopping 113mm longer, 67mm wider and 37mm taller than the car it replaces, with the wheelbase stretched 24mm.

It is also the most pumped M5 yet, compared to a 520i it is 70mm chubbier at its flared wheel arches. The ‘M5’ insignia on the C-pillar means you’ll know this is the fast one. 

Presence is not in question, then, but beauty? Not the right word. The G90 makes its predecessors — especially the original ‘E28’ — look demure. 

The cabin layout builds on the concept debuted by the iX electric SUV, with twin integrated screens and focus on technology and minimal buttons. Materials are mostly high quality and feel fitting for the M5’s asking price.

Practicality is not really a BMW strong point no matter which model you pick. See, BMW mostly makes the car equivalent of uber-stylish and skin-tight active wear which looks good and performs brilliantly, but sometimes you just want pockets and a bit of room for your… um… bits and pieces.

So while there are two cup holders up front and two in the back, the bottle holders in the doors aren't huge, the centre console bin is on the small side, there's a hidy-hole in front of the shifter, the glove box is just a box for little more than gloves and there's no other great cabin storage options.

Legroom in the rear is good but not great, too - I'm 191cm tall and have about 30mm between my knees and the seat back in my driving position. Middle-seat passengers will also have to straddle the drive shaft hump in the floor. Headroom is restricted in the back, too (you could blame the sunroof) with my hair just skimming the headlining (I do have big hair).

Under that power tailgate, the B5's boot capacity is 530 litres which is 15L more than its big sister, the B7. There are two plastic storage areas either side of the luggage space for wet things. While there is one USB outlet in the front there aren't any in the rear.

BMW has persevered with its twin-screen, minimal-button approach for its 'Operating System 8.5' in the M5. 

The 14.9-inch central touchscreen is bright, responsive and high resolution but the software remains a little strange. The main interface is classy but when looking for settings to adjust you’re presented with a Windows 95-esque panel of small square touch targets. It’s not intuitive. 

Wirelessly mirroring Apple CarPlay or Android Auto works a treat, at least. Digital climate controls keep temp adjustment persistently on screen and a shortcut to fan speed. The nipple-like vent direction adjustment grows on you, as do the digital vent sliders. 

The 12.3-inch digital driver’s display still doesn’t have the freedom of customisation and clarity of Audi’s interface. 

The M5 has two cupholders, a deep central storage cubby, door bins that swallow two 600mL plastic bottles and twin wireless charging pad that resolutely grips smartphones even under the sort of tummy-churning G-Forces this M5 can manage. 

Setting the M5 apart from the regular sedan is a unique centre console bunching 'M Drive' modes, 'M Hybrid' modes and other shortcut functions together next to the gear toggle and M-engraved crystal 'iDrive' controller.

Comfortable front seats are power adjustable with in/out, up/down lumbar support and have two memory positions. 

The 5096mm long M5’s back seat is very spacious. Headroom is good for those beyond 182cm (six-foot), the bench is extremely supportive, while leg and toe room are adequate.

A fold-down centre armrest has two cupholders and there are USB-C charge ports in the back of each bucket seat for a total of four. 

You can buy an accessory mount that holds tablets or smartphones for rear seat passenger entertainment, too.

When you look in the boot, BMW offering a Touring version of the latest M5 makes even more sense. The load aperture is big but the usable space is narrow; the sides intrude on load space. 

The 466-litre space will make fitting suitcases for an airport run tricky and, even with the 40/60 split-fold rear bench, you will struggle to fit a bike in the back. There’s no spare tyre, either.

The last M5 was well equipped but the new car is wanting for nothing. Australian cars have just about every option for $259,900, before on-road costs.

Australian M5s wear staggered 20-inch front and 21-inch rear alloy wheels paired with standard metallic paint, 'M Carbon Exterior' package (including carbon roof and rear lip spoiler), adaptive LED headlights and BMW’s 'Iconic Glow' illuminated kidney grille surrounds. 

Keyless entry, a heated steering wheel, heated and ventilated front seats, interior camera, powerful 18-speaker Bowers & Wilkins sound system, M seatbelts, four-zone climate control and a power tailgate are the cabin highlights. 

Optional extras are thin on the ground; you can choose from (eight) no-cost paint colours and all manner of 'Individual' shades (from $4100), four interior trims including classy 'Dark Oak' wood and four leather colours. There’s classic black ‘Merino’ leather, or you can have it dyed with a mix of 'Silverstone', red or 'Kyalami Orange'. 

Aside from that, the only major option is carbon ceramic brakes at a staggering $18,500, and an M5 Touring wagon costs $263,900. 

Though the M5 is more expensive than Audi’s closest rival, the RS6, the gulf isn’t huge considering you get a lot more punch in the BMW. Mercedes-AMG does not have an E-Class answer, yet.

Good value, then? Well, an equally potent Porsche Panamera is twice the price. So yes, in a sense.

The Alpina B5 uses the same 4.4-litre V8 engine found in the BMW M5 (and also the B7). But, and it's a big but, the M5 makes 441kW and 750Nm, while the B5 outdoes it with 447kW and 800Nm. Admittedly, the B5's torque arrives at the 3000rpm mark, while the M5's is all there from 1800rpm.

How does the B5 beat it? Alpina installed its specially developed twin turbochargers and intercoolers, a high-performance cooling system, a reconfigured air intake set up and a different exhaust system.

The B5, though, is a tenth of a second slower to 100km/h compared to the M5 with a time of 3.5 seconds, but it will blast on to a top speed of 330km/h while the M5 is limited to 250km/h in regular form and 305km/h with the optional M Driver's package.

Both uses the same ZF eight-speed automatic transmission with identical gear ratios, and both are all-wheel drive.

Unlike the Mercedes-AMG C63, BMW has kept the M5’s eight-cylinder heart and this has proven to be a good decision. 

The 4.4-litre twin-turbo petrol engine has been optimised with “a cross-bank exhaust manifold and optimised oil separation”, says BMW.

The V8 spins to 7200rpm though it isn't a screamer, outputting a full-bodied 430kW (5600-6500rpm) and 750Nm (1800-5400rpm).

Augmented with a transmission-mounted 145kW electric motor that can produce up to 450Nm, thanks to pre-gearing, maximum combined outputs are 535kW and 1000Nm. 

Weight blunts punch, though, so despite nearly 100kW and 250Nm more, the new M5 is a tenth slower to 100km/h than its predecessor (claimed), at 3.5 seconds for the sprint.

You can thank a 220kW/tonne power-to-weight ratio, worse than the old car's 233kW/tonne figure. The new G90 claws some time back with brute force, hitting 200km/h in just 10.9 seconds and goes on to a limited top speed of 305km/h.

You can choose from five powertrain settings, starting with 'Electric' and 'Hybrid' for everyday use, while 'eControl' lets you store battery power for urban use.

'Dynamic' provides the best balance, says BMW, while 'Dynamic Plus' is like a qualifying mode. Think maximum combined punch for up to 10 minutes, at which point you’ll have drained the battery. 

Driving in pure electric mode, the take-off can be a little jerky but the quietude and decent power make it pleasant. Power sources are combined expertly in Hybrid and giving it some stick in Dynamic is more than enough to make your passengers feel queasy.

The Alpina B5 needs petrol. By that, I mean it needs quite a lot of it if you want to enjoy it properly. What type of mileage does it get? Officially, it should use 11.1L/100km after a combination of urban and open roads, where as the M5 is set to 10.5L/100km.

That makes sense, the B5 produces more power and torque, and it's 85kg heavier than the M5 at 2015kg.

Our test car's trip computer was reporting 13.2L/100km after flying low over country roads and slow city piloting. The more time spent in the urban warfare that is the daily peak hour commute, the more that figure crept and hovered around the 15L/100km mark.

Electric-only range is rated up to 69km in WLTP testing, but the 18.6kWh battery is more likely to give you around 60km in real-world driving. It can be topped up in about two hours using an 11kW AC charger, or overnight on a three-pin socket. 

BMW includes both Mode 3 (public) and Mode 2 (home) charging cables with the M5. 

The M5 uses 3.2L/100km of 98 RON premium unleaded in ADR testing, corresponding to just 72g/km of CO2, so it should sail through the first rounds of Australian emissions regulations. 

Indulging in what the V8 has to offer sees that consumption spike, though. An enthusiastic road drive saw the M5 gulp 12.4L/100km, according to the trip computer.

Ok, stay with me here. For this next bit you'll need a fresh egg, a lounge chair, and it might be a good idea to have some plastic bags and carpet cleaner on hand.

First, in front of the lounge chair flatten out the plastic bag and place the egg on it. Next, sit down on the chair and very carefully rest the ball of your foot on the egg with as little pressure as humanly possible.

This is exactly how little force you need to apply to the go-pedal of the B5 to accelerate from a standstill to 60km/h in about five seconds.

If anything sums up the driving experience of the B5, it's that sense of effortlessness.

Stomp on that accelerator, and you'll be shot to 100km/h in 3.5 seconds, without a hint of broken traction thanks to the all-wheel-drive system.

The ride should have been terrible on 20-inch wheels shod in low-profile rubber (Pirelli P Zero 255/35 front, and 295/30 rear), but the Alpina-tuned air suspension is close to miraculous in the way it cushioned and censored the potholes out of Sydney's worst roads. Yes, it can be a touch floaty, particularly in the Comfort Plus setting, but this is benchmark-setting stuff for a comfortable ride.

Don't expect this beast to roar. Unlike the M5, the B5 gets its work done without deafening everybody around it. Sure, the B5's V8 sounds amazing when you push it, but it's not brash, not loud and not lairy. Buy an M5 or Mercedes-AMG E63s if you want to be heard half a block before you get home, but you won't get that with the B5 and its exhaust system.

The B5 also handles well, but I have to say the engagement factor is low. I piloted it effortlessly through the twists and turns of my country test circuit and roads which normally have me grinning like a maniac behind the wheel had me feeling a bit disconnected in the B5. That air suspension, the numb steering and pedal actions make it difficult to ‘feel' the road.

It's highways where the B5 is a king, but even at 110km/h there's the sense that this car is still fast asleep and won't get out of bed for anything less than 150km/h - making it perfect for Germany's autobahns, but maybe not for here in Australia.

The three M5 elements start with daily usability. We trundled out of Bathurst in electric mode, with the adaptive dampers (and other myriad settings) in Comfort. 

The M5 has steel springs, double wishbone front suspension and a five-link rear axle, all of which has been heavily reworked by the boffins at M. Naturally, the ride is firm, though in Comfort the body moves through its motions smoothly. 

The M5 is an effortless tourer, its eight-speed automatic shmoozing through ratios as it climbs and descends steep gradients. Wind and tyre noise insulation is good on coarse chip tarmac, though a bit more burble from the V8 would be appreciated. 

The M5 has nine adjustable parameters to wake it up: 'Drivetrain', 'Energy Recovery', 'Drivelogic' (gear shift aggression), 'Chassis', 'Steering', 'Brake', 'M xDrive', stability control settings and 'M Sound'. Favourite settings can be stored to the wheel-mounted M1 and M2 buttons. 

With the dampers still in Comfort the M5 remains fantastically capable with power delivery from the xDrive mighty rewarding on corner exit. Sport dampers sharpen the experience up further, amplifying the M5’s surprising agility. Thank the rear-wheel steer for this big sedan’s switchback performance. 

Step beyond the limit of grip, brake too late, or get on the power too early, though, and the M5’s mass reveals itself rapidly. It doesn’t help that the accurate steering is devoid of feel. The brake-by-wire pedal is too numb and light, as well, making it tricky to judge grip levels on the road.

Feel is less of an issue on a dry Mount Panorama circuit, where the M5 turns out to be a total pussycat. The all-wheel drive, consistent dynamics, strong brakes and well-tuned stability control make for an approachable but seriously fast sedan.

The responsive transmission will hold gears to redline and is eager on the downshift in its most aggressive setting while tactile shift paddles make commanding ratio changes yourself that bit more engaging. 

Prodigious punch out of corners is matched by the impressive consistency of the carbon ceramic brakes. The M5 pulled up for The Chase every time with minimal fuss, even from above 250km/h.

Similar credit goes to the 285mm front and 295mm rear Hankook S1 Evo tyres which remained consistent and predictable all day despite reaching temperatures over 130 degrees, according to the tyre pressure monitor.

The regular BMW 5 Series range scored a maximum five stars in 2023 ANCAP safety testing but this does not apply to the M5.

The M5 features nine airbags and a host of active safety systems, including auto emergency braking (AEB), blind-spot monitoring, rear cross-traffic alert, lane-keep assist, auto parking and speed limit assist. 

Lane-keep can easily be turned off via two taps but the other systems require more menu navigation, though are mostly unintrusive. A 'Track' mode disables lane-keep, AEB and other systems along with switching the central display off. 

The Alpina B5 is covered by BMW's three-year/unlimited kilometre warranty. Servicing is recommended every 12 months or 15,000km.

In Australia, BMW has moved to match other manufacturers in offering a five-year/unlimited kilometre warranty on all its cars. 

Servicing is recommended on a condition basis, with the M5’s multimedia system prompting a visit to the mechanics. BMW offers pre-paid service packs for five years/80,000km at a price of $5059 for the basic offer and $8152 for 'Inclusive Plus', which covers brake pad and rotor replacements. 

It is expensive next to a regular 5 Series but when you consider the purchase price and performance level, the M5’s service pricing is not astronomical.