Mercedes-Benz SL-Class vs Audi R8

What's the difference?

The SL's overall score is somewhat skewed by everyday concerns, and rules are rules - an average punter will find the price of this car somewhat confusing and the devil-may-care attitude to fuel consumption bewildering.

If neither of these things are a problem, then the SL63 makes plenty of - well, not sense, because it's not a particularly clever or considered car - but it fills a niche that not so long ago we all thought would go the way of the dodo.

The fact it sells so few examples is betrayed by some of the cabin amenities and the fact that Mercedes hasn't put much effort into reducing the car's weight to improve its consumption or sharpen up the handling.

The fact it still exists at all is pretty damn cool, though, and for certain people an SL63 purchase is the culmination of a lot of hard work.

If it is your dream car, the SL63 won't disappoint. Everyone who rode with me said it was mightily impressive, but you've got to really want it. When you're not far off buying a Ferrari California T or Aston Martin V12 Vantage S for the money, you'll need a real yearning for the three-pointed star to go this way. And if you do, good luck to you - you've probably worked quite hard to get here.

The Audi R8 V10 RWD and V10 Performance Quattro have their own personalities. I'm a big fan of the lower-powered rear-wheel drive car, but the Performance is the ultimate here with better brakes and that 330km/h top speed. Either way the R8 is a true supercar, but one that doesn't have to be driven gingerly as though something may break off.

The SL has always been completely unapologetic about its size and seems to be designed to accentuate rather than hide its length and width. The long bonnet screams power and prestige, and get out of my way, and is reminiscent of the little-loved McLaren SLR project of some years ago.

The size of the Mercedes logo on the huge front grille leaves you in little doubt about the brand of car that’s about to pass you at speed and some might say (okay, I would) that its large surface area is a little vulgar.

Like the SLR, the design doesn't seem to have a particularly cohesive strategy, with a number of Mercedes elements from around the traps that climb over each other. Roof up it looks awkward because of the gigantic posterior while with the roof down it looks overly long and, again, tail-heavy.

Folding hardtops are notoriously cumbersome and need a lot of room to hide them, but the silent operation is something to behold.

Elements that are worth deleting if possible are the dodgy 'Biturbo' badges. It's that kind of bling that gets people raising their little finger at you.

Lamborghini styling can look over the top, McLarens can sometimes appear delicate and fragile, and Ferraris seem to be everywhere, and even for me, begin to blend into one.

The R8, though, looks exactly how an Audi supercar should look – understated, tough and serious. Have you seen that Audi advert with the R8 on a dyno not wearing any pants? That sounds ridiculous but Google it because it sums up what the R8 is – a real car with a raw race car underneath, that's meant to be driven comfortably on the road and hard on a race track and the styling indicates that intent with little in the way of fanfare.

Well, there is that big window at the back which shows off the engine and the 'side blades' that surround the large vents carved into the side of the car to cool the engine.

The latest update has taken the design from the second-gen car which arrived in 2016 and added a new grille, front bumper, door sills and vents in the rear bumper. It's a more angular, sharper, and busier design with more vents and winglets than ever.

The R8 V10 RWD and R8 V10 Performance are close to identical in their styling. You can pick the Performance by its gloss carbon front spoiler, side sills, mirror caps and rear diffuser. The RWD has gloss black elements instead.

Which looks best: the Coupe or Spyder? That's a personal thing, but I reckon race cars need to have a hardtop roof, so it's the coupe for me, please.

Built using the 'Audi Space Frame' which weighs only 200kg, the R8 is 4426mm long and just 1240mm tall, but at 1940mm across it has a wide, planted stance.

“Practicality” is about as relevant to this car as a code of ethics is to a drug dealer or a contract killer, because the SL63 buyer is hardly worried about cupholders and boot space. For what it's worth, there are four cupholders in the two-seater cabin (which might explain why owners aren't worried about their liquid carrying prospects) and a minimum boot space of 364 litres and a maximum - with roof up - of 504, which is actually not bad.

Cleverly, there's a little robot-operated luggage cover inside the deep boot that stops your gear from being crushed when the roof goes down.

There's also space in the long doors where you might secrete a bottle of wine that would get a NSW Premier fired if he thanks you for it, and a bin in the console to hide your phone.

The R8 is a two-seater supercar and practicality isn't high on its 'to do' list with limited cabin storage in the form door pockets almost as small as my jeans pockets, two cupholders hiding under a trapdoor in the centre armrest, a hidey hole in front of the shifter containing a wireless charger and two USB ports and the glove box.

As for the boot – there are two: one in the nose with a 112-litre cargo capacity and another behind the mid-mounted engine with 226 litres.

Room for people, well you and a friend, is excellent. I'm 191cm (6'3") tall with a 2.0m wingspan and found the footwell deep and spacious, while head and shoulder room is also good.

The entry level R8 RWD Coupe lists for $295,000, while the Spyder version is $316,500. The R8 V10 Performance Coupe is $395,000 and the Spyder is $416,500.

It's in my view the best value supercar on the market. The Lamborghini Huracán Evo shares the same 5.2-litre V10, the transmission and the chassis (like Audi it's part of the Volkswagen family) and starts at $460K.

A Ferrari 488 Pista is pushing $600K, but the McLaren 570S is closer in price at $395,000 – although I find the R8 much less stressful and completely different to drive – read about that below.

Let's talk features. Coming standard on the R8 RWD Coupe and Spyder are laser LED headlights (new to the R8 for this update), 20-inch cast aluminum wheels (also new), a full leather interior (new) with heated and power adjustable RS sports seats, 12.3-inch instrument cluster, Bang & Olufsen 13-speaker stereo (new, too), sat nav, digital radio, proximity key and wireless device charging (new).

The R8 V10 Performance Coupe gets all of the features above but swaps the wheels for lighter, milled alloy rims, ditches the steel brakes for ceramic (pricey to replace, though), and adds other mechanical extras over the entry car such as Audi's magnetic dampers, plus a carbon-fibre reinforced polymer front swaybar.

What's missing? A central media screen would be good so your passenger can pick the music or follow the sat nav. Audi calls it a 'driver-focused cabin', but the Huracán has a media screen in the centre console.

I think there's a bit of advanced safety equipment missing, too – but that's in the section down further.

The SL63 is powered by Mercedes’ increasingly famous V8, with two turbos along for the ride to add oomph and cut the car's famous consumption, at least slightly. The 5.5-litre unit produces a massive 430kW and a scarcely believable 900Nm of torque.

All of that heads rearward via a seven-speed dual-clutch transmission that helps sling the 4.6m, 1848kg machine to 100km/h in 4.1 seconds.

There are two grades in the Audi R8 range – the entry-point R8 V10 RWD which has rear-wheel drive (RWD), and the R8 V10 Performance Quattro which has all-wheel drive (AWD).

Both obviously have V10 engines, it's a naturally aspirated 5.2-litre petrol unit (so no turbos here), but the RWD makes less power and torque at 397kW and 540Nm, while the Performance produces 449kW and 560Nm.

The V10 is mounted behind the driver's seat but ahead of the rear axle making it mid-engined car. The engine even has its own window and you can see it in there with its face pressed up against the glass.

There are two body styles as well – the Coupe and Spyder (convertible, roadster, just another word for a retractable soft roof). We'll get to the prices in the next section, but let's talk about the more interesting numbers such as top speeds.

The V10 RWD in coupe form can reach 324km/h and the Spyder can hit 322km/h while the V10 Performance Coupe and Spyder are both a smidge quicker at 330km/h.

Those are all go-straight-to-jail speeds in Australia, so if you're tempted to fact check my numbers then do it on a racetrack. Audi holds excellent track days – I've done them and you'll not only get to drive the R8 as fast as you can, the instructors will help you improve your advanced driving skills, too. Do it, it could save your life.

Acceleration from 0-100km/h is rapid – 3.7 seconds and 3.8 seconds for the V10 RWD Coupe and Spyder respectively, while the V10 Performance Coupe and Spyder can nail it in 3.2 seconds and 3.3 seconds.

The V10 engine has a cylinder-on-demand feature which can shut down five of the cylinders while cruising on a motorway, say at 110km/h. It's a fuel-saving system, but keep in mind this V10 loves petrol and lots of it – I've hidden that all the way down the bottom of this review.

Shifting gears in all R8s is a seven-speed dual-clutch automatic transmission.

Much as is the case with the price, there's no real way to soften the blow here - the SL63 drinks like a footballer on Mad Monday, except it does it every day. The official combined cycle figure of 10.2L/100km is quite easy to double, as we did, averaging 21L/100km in mostly flowing suburban traffic. In the car’s defence, the accelerator pedal spent a good deal of time near the firewall.

The SL does have stop-start to help reduce its considerable environmental impact.

That's like asking how many calories are in this pavlova that I'm about to push into my mouth? Seriously if you're asking then you shouldn't be eating it – or driving the R8.

But just for the record, according to Audi the RWD R8 uses 12.0L/100km in Coupe form and 12.2L/100km in Spyder guise after a combination of urban and open roads, while the AWD R8 of course will use more at 13.4L/100km for both Coupe and Spyder.

There are a number of impressive things about the way the SL drives. Firstly, astronauts will be familiar with the galactic thrust of the V8. It seems endless, seamless and ready to sling the big coupe into the outer atmosphere. Few engines of any kind can match the relentless go on offer in the SL and much of the credit should go to the seven-speed twin-clutch transmission.

When you jump on the brakes and shift down, the exhaust keeps the show going with angry crackles and pops.

Containing a torque figure like the twin-turbo V8's requires a lot of electro-trickery to stop you from being launched off the road. The great thing about all that stuff is that it works unobtrusively and smoothly.

Mashing the carpet in an SL without traction control would create much sound and smoke but little forward progress, such is the twist on tap. The SL has a range of modes from full-nanny (which is meant to keep you on the slippery Alpine road you've chosen to get you to some Swiss ski resort) while turning the dial all the way around to Race loosens the bonds.

It's in this mode you'll have the most fun and it does seem that the intermediate settings are a bit of a waste of time. Race mode does little to diminish the amazing ride quality provided by the active suspension setup, but relaxes the reins on the huge rear tyres. Exiting roundabouts is suddenly a huge laugh, with the tail cheerfully breaking traction and the two-mode exhaust thundering in a most pleasant way.

Better still is that when you jump on the brakes and shift down, the exhaust keeps the show going with angry crackles and pops, with more on the way when you lift off. There's little to match the aural pleasures of a properly tuned V8 and Mercedes has resisted the temptation to quieten it down on the outside and generate a fake noise for the inside. Although that would be stupid in a convertible, if you think about it.

The SL63, despite its AMG badge, isn't about all-out handling, of course. The Ferrari California would definitely show it how it’s done on a winding country road. The SL is more about flow, building momentum and rarely shifting down to second gear. The monstrous torque is enough to keep things rolling but should you wish for a bit more of the exhaust bellow, second is there for the taking.

Hustling the big convertible feels wrong, not because it can't do it, but because it's not really what it's for. Having said that, it offers a kind of fun that nothing else on Earth will provide, not even a Bentley GTC.

With the roof up, the SL63 is a quiet place but not remarkably so. The huge sticky tyres do the cabin's hush no favours, with an annoying roar on a wider range of surfaces than you might expect.

Roof down, it's hardly a paragon of virtue. A lot of wind noise reaches the cabin, even well below the huge speeds the SL can reach. So if you want to talk, it's windows up you'll need to deploy the mesh screen that bridges the roll hoops.

A race circuit is the best place to test the performance of an Audi R8. I've been lucky enough to have done this in the past, but for this update of the R8 the Australian launch was held on public roads and included a convoy of RS models such as the RS 6 Avant, RS 7, RS Q3 and TT RS.

Even then I think I was 'stitched up' because I began the day in the R8 V10 Performance Coupe but spent almost the entirety of my allocated time in roadworks at 40km/h before swapping to an RS Q3.

So, while I can't honesty comment about the dynamics on this updated R8 V10 Performance Coupe I can tell you that having driven every iteration of the R8 since 2012 that it's a weapon, with helicopter-like visibility out of that large front window.

If, like me, you think turbos are 'cheating' (superchargers are fine), then you'll love the linear power delivery of the R8's naturally aspirated V10, and while I love front-engined sportscars, nothing beats a mid-engined car for the feeling of balance and lightness in the nose while having the sound of thousands of explosions going off just behind your back.

Having AWD is not just great for acceleration and perfect traction from Audi's quattro system, I think it's a good safety feature in a supercar, and while only your judgements can stop things going pear shaped, the system will be there to help on slippery roads.

The following day was different. I was in the R8 V10 RWD, the country roads were superb and while it wasn't a racetrack it was enough to get a hint of the capabilities of the RWD R8.

While the R8 V10 RWD feels the same to sit in with the same great view, it feels different to drive than its faster sibling, in a good way. First there's the noticeable power difference – more than 50kW and 20Nm less – but also the lack of AWD makes the front end feel more pointable, and the car feel more like a traditional sportscar that pushes from behind rather than pulling from the front. Less power, but more fun.

The RS cars in our test convoy were all awesome machines, but stepping out of even the RS6 Avant and slipping down into the R8 cockpit was like getting into a UFO – it's so far ahead dynamically of any other Audi that all I could do was laugh like an idiot. Corners which were making an RS 7 really struggle, were handled effortlessly by the R8. And in a straight line it's a bullet in a barrel.

The Performance has the better brakes: 380mm ceramic discs with six piston calipers up front and 356mm discs with four piston calipers at the rear. The RWD has steel discs – 365mm with eight piston calipers up front and 356mm discs with four piston calipers in the rear.

Keep in mind if you are planning on track days, you'll find the ceramic discs costly to replace, and beside the stopping power of the steel ones is excellent.

And yet, on pot holed course bitumen the ride is a lot more comfortable than you might think and having driven the Performance in traffic it's a much nicer place to sit than the claustrophobic cabin of a McLaren 570S. You could honestly use the R8 daily.

ANCAP has not tested the Audi R8 so there's no star rating available. What we can tell you is that the R8 has a low level of advanced safety technology – there's no AEB, no adaptive cruise control, no rear cross traffic alert, nor blind spot warning, nor lane keeping assistance. That's the reason why the score is so low here.

The R8 does have electronic stability control and ABS, and active roll over protection, plus six airbags, although the Spyder doesn't have curtain airbags.

The SL63 is covered by Mercedes' three-year/unlimited kilometre warranty. And, er, that's it.

The R8 is covered by Audi's three-year, unlimited kilometre warranty which not only falls behind in duration compared to mainstream brands but also its direct rival Mercedes-Benz which now has five-year, unlimited kilometre coverage.

Service intervals are every 12 months or 15,000km but unlike other Audi models there isn't a three-year or five-year plan available.