Mercedes-Benz AMG GT vs KTM X-Bow

What's the difference?

This is no Lotus, but damn if it ain't a hell of a good time, and proof positive that electrification can enhance the V8 experience, rather than ruin it.

Okay, so rain is not your friend. Neither is brutal sunshine, strong winds or any speed bump anywhere. There are probably a handful of times you'll want to drive it, and when you do you will definitely get hit in the face with rocks and bugs, and spend most of your time wondering just how the hell this thing is legal.

And yet, we are hopelessly, head-over-heels in love with it. It's an absolute weapon on a track, a joy on anything even resembling a twisting road and it is one of the few genuinely unique cars on the road today. And the fact it exists at all is a cause for absolute celebration.

It's a mean, but somehow still sleek, looking beast, this big AMG, but it's also immediately recognisable as a thing of intent.

Up front, there's the huge vertical-slat grille that looks like it drove straight out of a Stephen King novel, a massively domed bonnet, and these vacuum-like side intakes that look like they could suck in stray animals.

Then, at the back, there are twin dual-pipe exits (for four in total), and an automatic wing that pops out of the rear bodywork. And all of that's capped off with these massive 21-inch forged alloy wheels hiding golden ceramic-composite brakes.

Mean, yes, but not quite as aggressive as you might expect the most powerful AMG to date to come across, perhaps.

Inside, it's more subdued again, with the AMG presenting a pretty passenger-friendly space, with all the Benz tech you'd imagine, including the massive screens, and — thanks to its air suspension and drive modes — the ability to tailor the ride to your liking, meaning a comfortable and premium experience, despite the power under your right foot.

The X-Bow R is built for purpose in the most wonderful of ways. From the visible suspension components to the rocket-style exhausts, to the stripped-bare interior, it's fairly obvious that form came a distant second to function in the X-Bow's design process.

And, for us at least, that's a tremendous thing. It looks raw and visceral, and a bit like Harvey Dent post-fire - you can see all the normally hidden components doing their thing. It's mesmerising.

It's not overly practical, given its size, with AMG locking in a four-seat configuration with a fixed rear pew that limits boot space. You can get folding seats, but only as part of an option package.

What you're left with is a vehicle that stretches 5054mm in length, 1953mm in width and 1447mm in height, but that serves up rear seating for only two – albeit very comfortably – and, because of the electric battery and motor being housed at the rear, boot space of just 335 litres.

There is triple-zone climate control, and the rear seating is lounge-like and luxurious, while the up-front space is ample for two full-size riders, too.

There's no spare, with AMG's 'Tirefit' puncture repair system on board.

Short answer? It's not. People are unlikely to test drive an X-Bow R and start looking for cupholders and storage space, but if they did, it wouldn't take long.

Aside from the twin seats, a four-point racing harness, a high-mounted gearshift, a pull-lever handbrake, and detachable steering wheel, the cabin is as bare as Old Mother Hubbard's cupboard.

Luggage space is limited to what you can carry in your pockets (though wearing cargo pants will help) and even getting in and out of the thing takes some fleet-footed antics. With no doors you need to literally jump in. And the side sills are only rated to 120kg, so heavier types will need to avoid stepping on them at all, and instead attempt a kind of running leap into the cockpit.

Keen readers of this site will recognise this as the area where we outline the many and varied features that come along with a normal new car purchase, but that's just not going to work this time. In fact, it'll be considerably easier to talk about what's missing, so let's start with the obvious: doors, windows, roof, windscreen. All conspicuously absent from this weird and utterly wonderful X-Bow.

Inside, you'll find two thinly (and we mean thin - we've seen thicker contact lenses) padded seats fixed into the tub. You'll also find push-button start, a digital screen reminiscent of those found on motorbikes (KTM is an Austrian-based motorcycle company, after all) and a pedal box that slides backward and forwards to offset the height of the pilot. Oh, and that steering wheel can pop off to make getting in and out easier.

Climate control? Nope. Stereo? Nope. Proximity unlocking? Well, kind of. With no doors, you'll always find it unlocked when you enter its proximity. Does that count?

But what it does have is a turbocharged two-litre engine. And in a car that weighs a sprightly 790kg, that means it's quick, pulling like a rabid sled dog in every gear, rear tyres chirping with every change.

It's not just what's under the bonnet, but what's at the rear axle, too.

But let's start at the front, shall we? Here, a familiar twin-turbo V8 engine lurks, producing a potent 470kW and 900Nm, which is fed through a nine-speed automatic, complete with paddle shifters and several drive modes, including the traction-limiting 'Race'.

But that is then joined at the rear by an electric motor with its own two-speed transmission, and which produces 70kW and 320Nm – or up to 150kW for 10-second blasts under heavy acceleration.

Combine both, and you're tapping into around 620kW and in excess of 1000Nm, enabling a sprint to 100km/h in just 2.9 seconds, and a flying top speed of 316km/h.

The X-Bow R's power comes from an Audi-sourced, turbocharged 2.0-litre engine, paired with a VW Group six-speed manual transmission (and one of the stubbiest gearsticks in existence). That mid-mounted marvel produces 220kW at 6300rpm and 400Nm at 3300rpm, and ships it off to the rear tyres with the assistance of a Drexler mechanical limited-slip differential.

Thanks to its lithe and lightweight body, that's enough to propel the X-Bow R from 0-100km/h in a blistering 3.9 seconds, and on to a top speed of 230km/h.

Fuel efficiency is surprisingly impressive for a vehicle this big and powerful, with Mercedes claiming 7.7L/100km and 175g/km of CO2 on the combined cycle.

Helping that is a the 6.1kW battery, which delivers just 12km in all-electric driving range, but helps reduce overall fuel use.

This AMG is AC power only, meaning you can't recharge using fast chargers, but the brand says its secret trick is its ability to recharge itself using captured kinetic energy incredibly quickly – largely negating the need to plug in unless you want to unlock that EV range – with Merc suggesting that, on a race track for example, the battery will discharge and charge itself continuously as you're lapping.

KTM lists the X-Bow R's claimed/combined fuel figure at 8.3 litres per hundred kilometres (though we were managing mid-12s after an, ahem, very spirited test), with emissions pegged at 189 grams per kilometre.

The X-Bow R is also fitted with a 40-litre fuel tank, accessed via a side-mounted inlet. Instead of a fuel gauge, expect a digital reading showing how many litres you have left.

There's a lot of big numbers surrounding the Mercedes-AMG GT63S E Performance, but let me throw another one at you – 245km/h.

That was the high score I saw pop up on its digital speedo as the big and electrified Mercedes flew down the main straight at Sydney Motorsport Park (formerly Eastern Creek), before my courage ran out and my foot found the brake.

That kind of velocity is mind-bending in a vehicle this big, and so is the way that power is delivered, with the AMG's big brain deciding how and when to maximise power from the engine and electric motor to deliver a constant surge of torque that shoves you back, and the GT63S E Performance into the future.

But big acceleration is hardly surprising with that much power. What is a little more impressive is how easy this four-door supercar is to wrestle around a racetrack.

Sure, the feeling-out process is a little more involved, as you figure out how and when you'll feel the weight shifting, and as your brain struggles to compute how what's happening is even possible, but after a couple of laps the AMG settles into an easy, flowing rhythm that, while never feeling light on its feet, also doesn't feels like you're piloting a bus.

At least part of that is down to the wizardry on board, like the 'AMG Air Suspension', the rear-axle steering and the limited-slip diff, all of which combine to make the GT63S feel tighter and sharper than it would otherwise.

But it's also partly down to the prodigious power on offer – perfect corner entry and exits are less relevant when you have a cruise missile strapped to your right foot that doesn't just quickly make up for any driver errors, but shrinks the space between corners to the blink of an eye.

Yes, it's heavy, and there isn't much that's pure about the go-fast experience, but it left an ear-to-ear grin on my face, and isn't that priority one for any new AMG?

How does it drive on the road? That I don't know, as this was a track-only drive day. But we will get one on a proper test soon and let you know.

It couldn't be more Fast and Furious if it had Vin Diesel growling under its (non-existent) bonnet. We have technically driven faster cars, but we have never driven anything that feels quite so fast as this utterly insane X-Bow R.

Climb in, strap into the four-point harness and select first via the surprisingly easy-to-manage gearbox and clutch set up, and, at slow speeds, wrestle with the dead weight of the completely unassisted steering, and it's immediately clear that this is a driving experience like nothing else currently road-legal in Australia. Even at walking pace, the X-Bow R feels poised for an assault on the future, and it attracts attention on the road like nothing else we've ever driven.

Its road-scraping ride height and diminutive dimensions make tackling traffic an intimidating prospect, with regular hatchbacks suddenly taking on truck-like proportions and actual trucks now looking like passing planets. There's a constant concern that you're sitting well below the traditional blind spot, and that you could be crushed at any moment.

Combine all that with the bad weather that cursed our final day of testing, and the X-Bow R is all sorts of watery hell. It is truly homicidal in the wet, too, with the back end breaking grip at the slightest provocation. And the turbocharged 2.0-litre offers plenty of that.

But on a sunny day, and on the right road, it's pure driving bliss. The acceleration is brutal, the grip endless and the Audi sourced gearbox an absolute treat. And it pulls in every gear, tackling 35km/h corners in third and absolutely blasting out the other side.

Cornering is scalpel sharp, and the steering - so heavy at slow speeds - is light and efficient at pace, requiring only the most minuscule of movements to bite into a bend.

It is anything but perfect in the city, and even a light sprinkling of rain will have you seeking shelter (and a refund), but on the right road, on the right day, there are few if any cars that offer the kind of razor-sharp thrills and intoxicating excitement of KTM's monstrous X-Bow R.

Next to none. There is no ABS, traction or stability control. No airbags, powered steering or ISOFIX attachment points, either. If you break traction (which, in the wet, is more than a little bit likely) it'll be up to you to ensure you straighten up again. Helpfully, there's a ton of grip from the Michelin Super Sport tyres.

As part of the compliance program, Simply Sports Cars (the company responsible for introducing the X-Bow R) actually crash tested two cars in Europe, and raised the ride height by 10 millimetres. Oh, and there's now a seatbelt warning sign, too.

The GT63S E Performance is covered by Mercedes' five-year, unlimited-kilometre warranty, and you can pre-pay your service costs to keep the prices down.

Service pricing for the electrified model is yet to be confirmed.

The X-Bow R is covered by a two-year, unlimited-kilometre warranty, and while service prices aren't capped, Simply Sports Cars estimates an average serve cost at about $350.