Audi S5 vs Mercedes-Benz C43

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 new AMG C 43 may lack the drama and excitement we’ve come to expect from the German performance brand, but that doesn’t mean it’s a bad car. Yes, it could be more extroverted and the ride could be improved, but this is still a sharp-looking sports sedan with loads of punch.

This is a car that speaks to its times, with ever-stricter emissions regulations making it harder and harder for car companies to produce loud, wild and charismatic cars. So Mercedes-AMG has worked within those boundaries and come up with a car that retains at least some of those core elements that has made the brand so desirable over the years.

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

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.

Mercedes has created something of a problem for itself with its decision to introduce AMG styling packages for the majority of its range, including the C-Class.

It means the C 43 has to walk a fine line between looking like a unique AMG model, rather than just a C300 with a bodykit and not out-doing the C63.

To that end it has AMG’s now familiar grille with vertical bars, the unique and complex-looking 20-inch alloy rims and a small lip spoiler on the boot. But otherwise it is surprisingly understated for an AMG, lacking the more obvious and muscular stance of previous AMG offerings.

Inside, there’s a similar theme, with the typical Mercedes-Benz luxury appointments but with a sportier, AMG twist. The steering wheel is chunky and comes with AMG branding, metallic shift paddles and a pair of rotary dials/buttons that allow you to alter the various drive modes and settings.

The one on the right allows you to switch between the pre-set Comfort, Sport, Sport+ and Individual modes, while the one on the left can scroll between the various individual aspects to tailor the settings to the conditions.

In typical modern fashion the design is tech-laden, with a digital display for the instrument panel (that can be switched between various graphics) and a large, tablet-style central multimedia touchscreen that controls the majority of the car’s non-driving functions.

…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.

The new C-Class has grown slightly in size compared to the model it replaces, most notably with a 26mm increase in the wheelbase which you can feel in the cabin.

The front seat space is good, with excellent adjustability for the power-adjustable seats and steering column. I had no trouble finding my ideal seating position which makes for a more enjoyable and uncompromised driving experience.

Rear space is a bit tighter (which is typical for this segment/size of vehicle), but thankfully the standard seats do have very deep sculpting in the backs which allow for more knee space and foot room.

However, at approximately 180cm (six-foot), I wouldn’t like to sit behind my seating position for long periods as my knees were touching the seat back, and headroom is compromised with the panoramic glass roof.

In terms of small item storage there’s a lidded console box in between the front seats as well as a pair of cupholders and a small tray where you can place your mobile phone.

It’s worth noting, though, that early examples of the C 43 in Australia do not have a wireless smartphone charging pad, with that reportedly being introduced from February production.

While that’s good news, it’s not really competitive in this day and age to offer a car costing six-figures without such technology.

There’s also only a single USB-C power outlet in the front, which is another disappointment, but there is a pair in the back.

Mercedes does win some points back for a respectable 455-litre boot, which has a nice wide load opening that will make packing luggage easier.

We’ll get to the major change under the bonnet shortly, but another significant alteration for this latest C 43 is the price.

It now starts at $134,900 (plus on-road costs), which pushes it well above its market rivals, the BMW M340i xDrive and Audi S4, which start at $104,900 and $106,200, respectively.

However, Mercedes has added more technology under the bonnet and loaded the C 43 up with standard equipment, including its '4Matic' all-wheel drive system, adaptive damping, rear-wheel steering and 20-inch alloy wheels.

In terms of creature comforts, the C 43 is well-appointed, with leather upholstery, a head-up display, augmented reality navigation, a panoramic sliding sunroof, and a Burmester 3D surround sound system.

There are two option packages for the C 43. The 'Digital Light Package' costs $2400 and adds Multibeam LED headlights with 'Ultra Range' highbeam, 'Adaptive Highbeam Assist Plus' as well as active light function and cornering light function.

The 'Performance Ergonomics Package' includes AMG Performance front seats, an AMG Performance steering wheel in Nappa leather and microfibre and the 'AMG Track Pace' system for an additional $5200.

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.

The biggest talking point about this new car is the engine, with AMG downsizing from the old C 43’s six-cylinder to a 2.0-litre four-cylinder turbocharged petrol engine.

But it’s not just any turbocharged four-pot, because it is fitted with technology that Mercedes claims has been inspired directly from its Formula One team.

While the F1 team engine facility is based in England, this engine was designed and developed by the Mercedes-AMG team at its Affalterbach headquarters, but the concept of the electric turbocharger reportedly comes from the engine that powered Lewis Hamilton to multiple world championships.

The electric exhaust gas turbocharger - to give it its official name - uses a small electric motor on the turbocharger shaft to spin up the blades without having to wait for any exhaust gases to pass through it first.

To power the electric turbo the C 43 is equipped with a mild-hybrid 48-volt electrical system.

Mercedes claims this means reduced lag and improved throttle response for a sportier driving experience. 

It also helps make this small engine produce big amounts of performance, with AMG extracting 300kW of power and 500Nm of torque from this 2.0-litre, which is more power than the previous six-cylinder C 43 managed.

The engine is paired to a nine-speed multi-clutch transmission, which isn’t a dual-clutch with a pair of clutches operating on every second gear ratio, but instead uses a “wet start-off clutch” for better take-offs and smoother shifting on the move (at least in theory).

Power is sent to the road via all four wheels thanks to Mercedes’ 4Matic all-wheel drive system.

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.

Despite the smaller engine you can hardly call the C 43 miserly, with a claimed combined urban/highway cycle rating of 9.1-litres per 100km. That’s only a 0.2L/100km improvement over the old six-cylinder.

On test, which included a return trip from Sydney to Bathurst via motorways and some dynamic back road driving, we saw a return of 11.8L/100km on the car's onboard computer.

While hardly hybrid-worrying, it’s impressive to think that driven modestly, such a potent engine can return a single-digit fuel figure.

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.

Let’s start with the good news. The new Mercedes-AMG C 43 is a quick car. The engine may be small in size but the electric turbocharger does its thing and provides plenty of punch.

You can get a performance boost, too, thanks to the belt-driven starter generator, which acts as a mild hybrid and gives you a surge of 10kW for a brief period if you need a sudden burst of extra speed.

The chassis is well-sorted, too, at least from a dynamic point-of-view. The rear-wheel steering can provide up to 2.5 degrees of turning, which improves handling at speed and manoeuvrability when parking.

However, there are some less-impressive elements to the C 43, too. The obvious one is the drama, or rather the lack thereof.

As I said at the beginning, the C 43 has never been as wild or raucous as the V8-powered C 63, but when you buy an AMG there’s a rightful expectation that it will provide some thrills.

The C 43 simply doesn’t have that character about it. Yes, it’s fast, but it produces that speed with efficiency rather than excitement.

And it’s not an engine size problem, because even the 2.0-litre four-cylinder A 35 and CLA 35 offer more ‘wow factor’ than the C 43.

Yes, the engine makes noise under acceleration (and it can be altered between discreet and sporty) but even at its best it sounds muted and lacks the evocative tone of a V8 or six-cylinder engine. 

Another disappointment is the transmission calibration, with the gearbox awkwardly shifting out of first gear on multiple occasions during our test drive.

In the taller gears it felt smooth enough cruising along, but given its low speed shifts we’d like to spend more time in the urban environment before passing final judgement. 

The other notable element of the driving experience we struggled with was the ride quality. While fine on the smoother motorways, our test drive included time on some patchy country back roads and the C 43, even in the ‘Comfort’ suspension setting, was simply too firm.

Riding on low profile tyres, the adaptive dampers struggled to isolate the cabin from the imperfections in the road, leading to a fussy ride at times.

Overall the C 43 is a good car, but it feels like there are still some areas where Mercedes could improve it to make it really live up to the AMG badge.

The C43 gets a comprehensive list of safety equipment that leaves little out. Obviously there are the usual passive safety items, like 10 airbags, including dual-front combined pelvic/thorax airbags and a front centre bag that drops between the front seat passengers to minimise the chances of a head clash.

Also included as standard is autonomous emergency braking front and rear (covering speeds between 7.0-200km/h), adaptive cruise control with active stop/go, a 360-degree parking camera, 'Active Parking Assist', 'Active Lane Keeping Assist', 'Blind Spot Assist' and, of course, anti-lock brakes with 'Brake Assist' and 'Adaptive Brakes' with Hold function and electronic stability control.

Also included are dusk-sensing LED lights, rain-sensing wipers and run-flat tyres with tyre pressure warning.

The C43 also comes equipped with Mercedes’ 'Driving Assistance Package Plus', which adds even more safety gear. This includes 'Active Blind Spot Assist', 'Active Brake Assist with Cross-Traffic Function', 'Active Emergency Stop Assist', 'Active Lane Change Assist', 'Active Lane Keeping Assist', 'Active Steering Assist', and 'Active Stop-and-Go Assist'.

While the C43 hasn’t been specifically crash-tested, the latest C-Class was rated by ANCAP with a five-star score for all models except the upcoming C 63 S E Performance.

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.

The C 43 is covered by Mercedes’ five-year, unlimited kilometre warranty, which has become the new standard for the luxury car market.

Service intervals for the car are at 12 months/25,000km, which is on par with industry standard.

Mercedes-Benz Australia will offer a service plan for the C 43, prices were yet to be confirmed at the time of publication but the company has indicated it will be similar to the C300. 

That means $550 for year one, $900 for year two, the third service costs $1000 and the fourth year service costs $2450 - for a total of $4900 for the first four years of ownership.