Audi S5 vs Mercedes-Benz C63

What's the difference?

The Audi A5 remains a convincing option in the premium mid-size sedan category, even with the near-$10K price increase over its equivalent grade A4 predecessor.

Even in its base spec, it’s a lovely thing to drive and adds enough new kit to be a reasonable option when it comes to value. In terms of tech usability, it stands out from rivals. Practicality is still king for Audi.

But for the heart-over-head types, the S5 is fast and fun while remaining a comfortable cruiser and the price is decent. On a personal note, a six-cylinder wagon? That's a big yes from me.

For the time it’s available, it’s hard to go past the value on offer in the S5 Edition One. Getting an AWD V6 with that kind of capability for under $100K is something that's sure to tempt buyers. If it doesn’t, we need to take a good look at ourselves.

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

The Mercedes-AMG C 63 S Aero Edition is an absolute beast of a car, but it comes at a pretty hefty price. Yes you get a lot of performance, and the fact there are only 63 examples being made for Australia and New Zealand could be enough to get you to sign on the line. For me, though, if I was after a C 63, it’d have to be a wagon. It doesn’t need an Aero pack to look better.

The A5 incorporates Audi’s new design language in a way that makes the 2026 model stand out from Audi’s older offerings, but we won’t know how well it works in the family until more new-gen Audi cars arrive.

For now, the A5 is a generally handsome car. It very much looks like an Audi from the front, even a recent A4 if you only very quickly glanced.

The aforementioned S line styling does plenty in making even the base Audi A5 look like a properly luxe thing. There were a few double-checks at the launch to make sure drivers were getting into the right cars.

Fortunately the new car’s designers refrained from busying up the car with trim, the only big features being the side vents at the front.

But even in Avant form the S5 looks athletic, quad-exhausts in the lower bar and the angular rear bodywork moving away from the previously softer, more rounded look Audi had gone with before.

Inside, the changes are arguably more obvious. The A5 is now much more ‘screeny’ than before, especially if optioned with the passenger-side touchscreen.

It’s still decidedly Audi in its layout and design, with geometric shapes on the steering wheel, screen housing, door cards and even on the gear shifter, which is no longer the more traditional handle-type.

I’ve never been the biggest fan of the current C-Class Coupe’s styling. To me, it has always looked a little droopy, a little melted at the back. 

I have to say, the Aero Edition has changed my opinion somewhat, as the new graphic elements help lift it up a bit, visually raising its rear up like a stretching cat, tail in the air. I’m still not 100 per cent on it, but to my eye it’s better.

The carbon-fibre trim elements that have been added to the exterior certainly add some menace to the look, too, and I simply can’t help but constantly notice out of the corner of my eye the AMG pressing in the staggered, dished rims. At a glimpse, from a distance,  it looks like rim damage, but thankfully it’s not!

The staggered set-up does really add some width and mongrel to the look, as if it needed more, with its open maw lower bumper air dam, and the signature 'Panamericana' grille treatment which looks like an evil character out of a movie. If you know the one I’m talking about, let me know in the comments.

As much as the look matters when it’s parked in your driveway, it’s the cabin that arguably matters more, right? That’s where you spend your time, after all. Check out the interior images to see if you think it lives up to the exterior look.

…and that gear selector is a bit indicative of the new A5’s interior. It’s now more of a switch that requires a little more attention than the traditional shifter, just like the way the more screen-focused interior requires a little more of your eyeball time than physical buttons.

Don’t get me wrong, as far as screens in modern cars go, Audi seems to have made it as easy as possible to use the new-gen software in the A5. The menus are clear, there are good shortcuts and there’s no lag… but buttons are always better when your focus needs to be on the road.

Fortunately the driver display is nice and clear, it’s a good update on Audi’s ‘Virtual Cockpit’ and you can set it to display important information without looking too busy.

Ergonomically, the way the central screen is angled towards the driver, the centre console layout and the small control panel on the door for lights, mirrors and the like all seem to be well considered and mean you don’t have to awkwardly reach for anything.

There are a few quirks specific to the A5 and S5, one being that if you opt for the panoramic sunroof, it comes with a transparency switch rather than a physical cover, so it doesn’t do much to keep the light out.

It’s also good to note that the passenger screen - again, if optioned - turns to privacy mode when playing media so as to not distract the driver. Pretty handy!

Behind the front row, a regular-sized adult should have enough room to sit comfortably for a decent amount of time without feeling cramped. The light through the sunroof comes in handy here.

Behind that is a 445L boot in Sedan form, or 1299L with the rear seats folded down. As an Avant, the space increases to 448L and 1396L respectively.

No two-door coupe is going to offer you the space and comfort of a sedan or wagon, that’s just a fact. But that only matters if you plan to actually use the rear seats. If you don’t, then the Coupe version of the C 63 S might be perfect for you.

Even so, I managed to (only just) squeeze myself between the seat and the door opening to slide into the rear row. This won’t be easily achieved by all attempters, especially on the driver’s side.

Let’s just say I probably looked like I was doing something very weird to the driver’s seat as I spider-manned my way in. 

The rear space is tight for someone my height (182cm/6’0”) behind their own driving position, with knees hard-up against the seat in front and not much headroom (my noggin’ was brushing the ceiling) or toe space (size 12s don’t fit so well) to speak of.

It’s certainly a selfish car. Or maybe it’d be fine for smaller kids. There are two spaces in the back, both with ISOFIX child seat anchors and top-tether points.

But there is storage in the back - cupholders and storage caddies either side of the seats, though the storage situation improves in the front zone, with bottle holders in the doors, cupholders between the seats, loose item storage under the media screen and a covered centre armrest bin, too.

The front cabin is a special looking place, with carbon-fibre abounding across the dash and nice trim on the doors. The AMG steering wheel is a sight to behold - it’s a flat-bottomed unit with carbon-fibre and Dinamica (that’s Benz talk for microsuede) trim: perfect for sapping sweat as you manhandle the C63 through the bends.

The seats are AMG Performance sports units up front, and the trim used is reserved for this model specifically: Nappa leather with yellow stripes. There are yellow details elsewhere, including on the rear seats, centre console and dash, and it certainly adds some visual excitement.

Media is controlled by a 10.25-inch display and Mercedes-Benz’s touchpad control system, but there is no touchscreen - rendering the Apple CarPlay and Android Auto smartphone mirroring technology somewhat tedious.

I’ve always had a gripe with screens that don’t allow touch but feature the tech that’s designed to transfer your phone’s screen to the media unit, and I can tell you the longer you spend twiddling the dial to get where you want to go, the more annoying it becomes.

The Burmester sound system has 13 speakers and is rather good, but I prefer the sound from the standard fit variable sports exhaust. So maybe that quibble with CarPlay isn’t that big a deal.

And if you just want to charge your phone, and there’s a second USB port up front, as well. Note: in non-Aero Edition C 63 models without the carbon-fibre interior pack, you also get Qi wireless phone charging, but it’s deleted from this variant and any model with the carbon pack.

The driver has a 12.3-inch digital info display to show where you are and what the car is up to, and there’s a head-up display as well. Yep, there’s standard sat nav with live traffic updates (and even live fuel price updates) - it’s just a shame the maps still look early 2000s-spec in 2D layout.

Cargo space is okay. The claimed cargo capacity or boot volume is 355 litres (VDA) with the rear seats in place. That’s small for a coupe of this size, and the shape of the boot (with a hump behind the rear seat) isn’t great as things do move around quite a bit.

But, thankfully, Mercedes has included its clever foldable storage box system under the boot floor - it goes where you might usually expect a spare wheel, but there isn’t one in this car. Instead you get Mercedes’ 'Tirefit' repair kit with an electric pump.

Look, I’m not likely to ever be in the position to say that a car that costs $188,600 plus on-road costs is “good value”, but to be honest, if you’re in that position, you’ll be getting plenty of car for your cash.

The Carbon Edition of the C 63 S Coupe adds $17,200 over the standard version of the high-performance two-door, but it adds a bunch of extras to help justify its price. A car like this is always going to be seen by some as a profligate purchase, right? You need to be able to justify spending an extra MG3’s worth of cash on this Edition. 

The noticeable exterior bits include an AMG Performance rear spoiler, a model specific front lip, rear diffuser, and side facings for the rear apron air vents. Carbon-fibre is used in the front apron A-wing, the side sill inserts, rear diffuser insert, rear spoiler and the side mirror casings. 

There’s more carbon-fibre inside the cabin, which we’ll cover off in the interior section. Other additions over the standard C 63 S Coupe include ceramic composite front brakes (402mm six-piston) and 360mm single-piston rear brakes, and there are “ultra-lightweight” AMG forged 'Matt Black' alloy wheels with 19-inch rims at the front and 20s at the rear. 

And in nice news, the car you see here has no optional extras fitted at all. The colour is 'Iridium Silver', one of only two options for this limited run model (the other available hue is Polar White, and both come at no extra cost).

Standard inclusions comprise leather interior trim, heated and electric adjustable front seats, dual-zone climate control, a 10.25-inch media screen with sat nav and smartphone mirroring, DAB radio, 13-speaker Burmester sound system, 12.3-inch digital driver info display, head-up display (HUD), ambient lighting, and performance items like active dynamic engine mounts, an adaptive AMG performance exhaust, a rear differential lock, and adaptive sports suspension.

Plus there’s a full-spec safety offering which we’ll cover in the section below.

Thinking about what cars compete with this one? There’s the Audi RS 5 Coupe (from $150,900), the Lexus RC F (from $136,636), and the BMW M4 Competition (from $167,829). So the C 63 S - which is already expensive comparatively - looks positively pricey in Aero Edition spec.

The Audi A5 is powered by a four-cylinder turbo-petrol engine which powers the front wheels via a seven-speed dual-clutch automatic transmission. It makes 150kW of power and 340Nm of torque, and should, Audi says, propel the A5 to 100km/h in 7.8 seconds before (eventually) reaching a top speed of 248km/h.

The S5, in all its variants, is powered by a 3.0-litre turbo-petrol V6 which is assisted by a mild hybrid system. It produces 270kW and 550Nm, sending that to all four wheels via a similar seven-speed dual-clutch.

The S5 is much quicker as a result - 100km/h comes along in just 4.5 seconds according to Audi, before reaching a 250km/h top speed.

Open the shapely bonnet of the C 63 S and you’ll find a hand-assembled horsepower-monster engine with a printed name plaque to prove it.

The 4.0-litre twin-turbo V8 produces 375kW of power at 6250rpm, and 700Nm of torque from 2000-4500rpm. It runs a standard-fit nine-speed 'Speedshift MCT' (multi-clutch transmission) automatic, and it’s rear-wheel drive. And yes, that means it likes to boogie.

The claimed 0-100km/h time is just 3.9 seconds, and top speed is apparently pegged at 250km/h. Yeesh.

The name on the “Handcrafted by” plaque on this particular engine? Hat tip to you, Julian Rembold. This is quite a piece of work. 

Audi claims the A5 uses 6.9 litres of fuel per 100km, which should theoretically deplete the 56-litre fuel tank after 811km of driving. We couldn’t test this on the launch, but reaching claimed fuel efficiency figures remains an elusive challenge.

The S5, according to Audi, comes with an impressive 7.1L/100km figure in Sedan form, or 7.2L/100km as an Avant. That’s 788km and 777km of theoretical driving range if you’re up for a challenge.

High numbers are what AMGs are about. Sadly that’s the case not only for performance outputs but also fuel consumption.

The official combined cycle fuel use claim for the C 63 S Coupe is 10.3 litres per 100 kilometres, and you need to fill it with 98RON premium unleaded fuel, too.

On test? Well, across a mix of different driving - urban, highway, back road and spirited stints - I saw an 'at the pump' return of 12.2L/100km, while the digital readout stated 12.0L/100km.

Given the performance on offer, and how much I took advantage of it during my week with the car, that’s not bad…

Fuel tank capacity is 66 litres. So go easy if you know there won’t be a fuel stop for a while.

One of the first press cars I ever drove as an even younger lad than I am now was the circa-2017 Audi S4.

Without the perspective of all the many, many cars I've since driven, that S4 blew my mind a little bit with its combination of capability and refinement.

Now, with the context of most of the cars available to the Australian buyer in mind, it’s reassuring to get into this new generation and find that the mid-size Audi torch has been gracefully passed on.

Audi says the new generation, sitting on its new platform, has more focus on balanced driving dynamics, steering precision and steering feel. Without sacrificing comfort, Audi wants the A5 to be a sharper driver’s car.

It might not gel with the Euro tradition of a rear-drive executive sedan given the base A5 is front-wheel drive - the brand of course focusing on its quattro all-wheel drive system - but the A5 is decidedly agile for its size. 

Compared to the S5 especially, as the A5’S 1770kg plays the S5’s 2025kg in Sedan form (2040kg as an Avant). It’s a noticeable weight difference, and it makes the A5 more playful without getting properly ragged.

It also rides on smaller 19-inch wheels and would overall probably make for the better daily driver. Even without the all-wheel-drive traction and extra power the S5 offers, the A5 makes a good case for properly plush commuting. Its 150kW isn’t lacking by any means, and that 340Nm does plenty to help when overtaking.

Its suspension feels well damped, keeping the road’s imperfections out of the cabin without numbing the ride and leaving you without feedback. The steering is similarly direct without being too heavy, making the A5 feel athletic for its size.

But for all the A5’s strengths, there is something undeniable about a six-cylinder European sedan (or wagon). The S5 is heavier, sure, and therefore not as naturally nimble, but it makes up for it. And it’s not just the extra power and mild-hybrid assistance.

It’s a great highway cruiser for a start, but it also adds the confidence of all-wheel drive to a trip, which proved extremely useful on the very rainy winter day we tested it. It holds up well on rough surfaces despite the bigger wheels and extra heft, plus it doesn’t feel out of hand when cornering fast, rolling into a predictable understeer rather than quickly losing traction.

But if you’re in any way conscious of your budget, consider the Edition One. It doesn’t lack any of the key things that make the S5 great, and you get to pocket enough money to buy a second used car.

Just one word sprang to my mind when it comes to accurately describing the performance on offer from this car. The word is ‘brutal’.

Smash the accelerator and the power and torque on offer is enough to make your eyes feel like they’re not doing the right thing anymore. You get pushed back in your seat with a surge, and your ears are also rewarded with one of the best soundtracks in the automotive world. 

The engine builds pace with enormous intent, and the sound that comes from under the bonnet and out the back through the exhausts is addictive.

Yes, there is an active exhaust button which you have to press to make sure that you hear all that noise if you’re running around in 'Comfort' mode, and during my time with the car it was active the whole time.

I had some questions from neighbours over the week that I had this car about whether it was actually nice to live with on a day-to-day basis. And the answer is yes, if you put it in comfort mode it’s surprisingly amenable. 

The ride is really well sorted at pace despite having a bit of that trademark low-speed wobble that seems to afflict Mercedes products from A-Class through to the GLE SUV. But it wasn’t bad enough to really bother me, as most of my time was on highways and backroads.

The steering is direct and accurate. The only thing you need to be aware of is that you will lose traction at the rear axle when you put your foot down hard. And for the enthusiast that’s exactly what you want. 

I know I want to feel the thing squirm under throttle. It’s a rear-drive V8 coupe, after all. You want to feel like you’re a vein in its bicep muscle; you know, the one you see in a weightlifter’s arms – the one that wiggles around a lot. You want to have that. Right?

On the performance front it is exceptional. Twist the little dial on the wheel to 'Sport' or 'Sport+' (I didn’t sample 'Race' mode as I wasn’t at a racetrack), and everything feels like it’s had a protein shake.

Even so, in that mode it steers brilliantly, there's a nice feel through the wheel, and the ride, while stiff, controls the body brilliantly when you change directions. 

The transmission is very good, too. In Comfort mode it can take just a second or two at first to become accustomed to the idea that you want to drive aggressively.

But in Sport mode, or when you select the manual transmission mode using the trigger button on the steering wheel, you will certainly get the most out of the engine. That’s what I did when I was driving it in a ‘spirited’ manner.

If you are just after that high-end Coupe cruiser experience, it’s a relatively quiet car (provided the surface below isn’t the coarsest of coarse-chip bitumen), with enough luxuriousness to make it feel premium as well as sporty. That’s an important thing to consider, especially at this price point.

There is no applicable ANCAP crash test rating for the Mercedes C-Class Coupe, nor is there one for the C 63 specification. But when it was tested back 2014, the sedan scored five stars - as you’d expect.

It is comprehensively equipped in terms of safety technology, including auto emergency braking (AEB) with pedestrian and cyclist detection (from 7.0km/h to 70km/h) and it’s active for cars from 7.0km/h to 250km/h.

Plus there’s lane departure warning and active lane keeping assistance (from 60km/h to 200km/h), blind spot monitoring with 'Active Blind Spot Assist' that will stop you from veering into oncoming traffic, front and rear cross traffic alert, and adaptive cruise control (Distronic) with traffic jam assist.

The C 63 also features 'Route Based Speed Adaptation', which can adjust your speed based on where the car thinks you are on the map. Just note - if you’re driving through new tunnels that haven’t been flashed to your car’s nav (as happened to me in Sydney during my testing week) - then you could find the car dramatically braking for surface-level intersections. You can switch the system off, thankfully.

There are nine airbags fitted, and while you mightn’t use the rear seats much there are ISOFIX and top tether points for both positions (yes, only two).

Audi’s five-year/unlimited kilometre warranty is starting to fall behind the industry standard, though is about normal for a premium brand. On top of this, customers can opt to purchase extra years of warranty up to a maximum nine years which costs $3590.

Audi does also offer 12 years of bodywork manufacturing warranty against corrosion or perforation. There’s also five years of Audi roadside assistance.

Servicing intervals for the A5 come in at every 15,000km or 12 months, with customers able to purchase fixed-price servicing plans at a discount compared to paying per service.

A five-year servicing pack for the A5 Sedan is $3360, and for the S5 it’s priced at $3540.

Mercedes-Benz is among the minority of luxury brands now offering a five-year/unlimited kilometre warranty plan - most still have three-year cover. So that’s a tick.

And the service intervals are pegged at 12 months/20,000km. Another tick.

Plus you can either pre-pay your service plan in three-year ($3800), four-year ($6000) or five-year ($6550) plans - roll it into the finance package, and it won’t hurt quite as much.

According to Mercedes, the three-year coverage option makes for a $900 discount over pay-as-you-go servicing.

Roadside assistance covers the five-year new car warranty period, too. So Mercedes seemingly takes good care of its customers. But if you have any concerns or questions over reliability, problems, issues or complaints about the C 63, check out our AMG C 63 problems page.