Mercedes-Benz C300 vs Audi S3

What's the difference?

Over five decades, the Mercedes-Benz C-Class has pivoted between mastery and mediocrity, and all-too-often relied on that three-pointed star up front to win over buyers.

Thankfully, the W206 is one is one of the better generations. It's easier on the eye, comfier to travel in, more intuitive to use, safer across the board and a huge improvement to drive. On the evidence of the C200 and C300 launch grades, there's newfound depth and consistency to savour.

Sure, prices have gone up, the C200 could use a bit more power, the steering could benefit from a bit more feel, the odd build-quality glitch made itself heard and there's a fair bit of road noise at times, but overall, the C-Class now deserves to be at the top of your luxury medium sedan shopping list.

Particularly if you can afford to stretch to the rorty C300.

The updated Audi S3 Sportback is a fun-sized dynamo with impressive outputs and athletic road manners. It’s missing a few premium features, but its compact size paired with a gutsy engine makes it a compelling option for drivers who don’t want to compromise on performance (just space).

If you're checking out the new C-Class for the first time from the front, you'll probably think… hmm, it looks just like the old one, and that's largely true.

But a side view reveals proportions that have changed significantly, thanks to the more raked windscreen, shorter overhangs and cleaner lines, which give it a slightly smaller S-Class look.

Which is more in fitting with where Mercedes wants to place this car against its 3 Series and A4 competitors.

Additionally, the taillights are split for the first time, allowing for a wider boot aperture since the lid now contains some of the lighting elements.

The shrunken limo looks aren't just the whim of some designer or Mercedes-Benz marketing department copywriter, either.

Underneath is an albeit highly modified version of the latest S-Class' MRA2 platform, which results in the longest (at 4755mm) and widest (at 1820mm) C-Class in the series' 40-year existence, as well as the first with this level of electrification capability.

Height and wheelbase dimensions also see a stretch, by 8mm and 25mm to 1450mm and 2865mm over the previous model respectively, and to the benefit of passenger accommodation.

Speaking of which, get used to this new interior aesthetic and general layout – it's a look that's probably going to filter through to most coming non-EQ-branded Mercedes models over the next few years.

From S to C to future E and A classes and beyond. It's a rare instance of trickle-down economics actually working!

The S3 Sportback may be a small car, but its S design features, like the stylised blackout grille, matrix LED headlights, and 19-inch alloys with red brake calipers, give it a distinctly athletic and fun-loving vibe. It’s compact, but definitely not diminutive and carries serious road presence. It’s hot hatch meets fun-size.

Inside, the S3 looks fabulous. Integrated ambient lighting, a sharp dashboard treatment and a driver-focused cockpit all lend it a premium feel.

The front seats look properly sporty with their integrated headrests, and the quilted Nappa leather upholstery feels great, especially with the eye-catching red contrast stitching.

As for technology, it’s as high-end as you’d expect with a 10.1-inch touchscreen multimedia display and 12.3-inch digital instrument cluster taking centre stage.

The only drawback? No sunroof. Combined with the black headliner and compact cabin, it can feel a little gloomy at times. Still, it’s a cabin you’ll enjoy spending time in.

One of the best things about the new C-Class is that it's larger and therefore roomier than before. It's also higher quality, easier to use, more comfortable to sit in and - overall - more of a delight to behold.

In contrast, the old C-Class dash looked and felt like it was designed for a much cheaper car, especially compared to Audi's efforts.

Obviously related to the S-Class this time around, it's clear Tesla provided the inspiration for the twin floating screen look and layout, which are just right in their driver orientation and ease of functionality.

There's never really been anything wrong with Mercedes' old front seats, but these AMG Line items are both sumptuous and bracing, keeping their occupants well located ahead of the clever and thoughtfully laid out dashboard.

The brilliantly high-resolution MBUX multimedia and voice-recognition system now works as it should - intuitively and logically, with the screen menus simple to recognise and easy to use, and most without the need to get lost in confusing sub-menus. Just like BMW has managed for years.

If you want to change the instrumentation design, it's now a couple of clearly marked steps, using handily placed switchgear. The same goes for the superb climate control and audio systems. And the wireless Apple CarPlay/Android Auto connected faultlessly and worked a treat. Effortless see-and-push operation all round, backed by concise and classy graphics.

No more degree in Earth-to-Mercedes comm skills required to master this C-Class interior.

Yet there's just enough old-school Benz features to appeal to brand diehards, from the eternal door-card mounted electric seat controls and column-mounted gear shifter, to the deep centre console and turbine face-level air vents. They meld together beautifully with the advanced tech also on offer, like the optional augmented-reality head-up display with 3D-graphics.

Annoyingly, on one of our test cars, that tradition also extended to a couple of squeaks and rattles, proving that maybe Mercedes hasn't quite conquered all its past quality gremlins. And, like most luxury cars nowadays, endless ambient lighting choices are available of dubious taste.

Never mind. This is the finest C-Class front-seat environment since, well, probably the original W210 190E's of the 1980s.

And all those extra dimensions pay dividends in terms of interior space in the back seat.

There's plenty of knee room even with the tester sat behind their 178cm frame; head room is adequate even with the optional sunroof fitted, and there's ample shoulder space. So, it's more comfortable than any C-Class ever has been in terms of sheer dimensions.

Additionally, the rear backrest is well angled, while the cushion is deep enough to provide sufficient thigh support. But the centre perch is a bit of a squeeze for all concerned. Best avoided.

There's also added practicality to be found with the large and deep door pockets, front seat-back map pockets and folding centre armrest, that not only has a tablet holder, but when pressed in twice, also reveals sliding cupholders as well. Clever.

The C-Class rear seat is really lacking for nothing, with face-level air vents, overhead lighting, grab handles and coat hooks all highlighting the level of thought that went into making this a practical compact family sedan.

Plus, the C-Class comes with this folding ski port, which along with the folding rear seats, increases boot volume from 455L to, well, a lot more. While that's not quite as good as others like the BMW 3 Series, it's big enough for this car.

Note that there is no spare wheel, as the tyres are of the limited-distance runflat variety.

Like most hatches, the front row enjoys the most space. While it’s cosy, it never feels cramped. The seats are firm yet comfortable, thanks to their adjustability and expandable under-thigh supports. Access is fairly easy with wide door apertures, though the low seating position might earn a few grunts, especially from taller folks.

Storage up front is well sorted, with a glove box, a small centre console, a dedicated phone cradle and a couple of cup and bottle holders. It’s about what you'd expect for a car this size, but it's enough to keep things tidy.

There are plenty of charging options, with two USB-C ports in each row and a wireless charging pad up front.

The multimedia system is intuitive and easy to use. The touchscreen is responsive, and wireless Apple CarPlay connected without fuss and stayed connected all week. Wireless Android Auto is available, too.

Built-in sat nav is clear, and I love the way directions pull through to the digital instrument panel. The Sonos sound system? Pretty darn good. My son and I had more than one mini-concert on the school run.

As for the rear row, it definitely reminds you this is a small car. At 168cm, I found it on the cramped side of cosy and my husband just laughed when I asked him to try it! The wheel arch also cuts into the door aperture, making access a little awkward. Best to think of it as occasional adult seating. But given the size, that’s no surprise.

Amenities in the back are decent with a couple of map pockets, cup and bottle holders, as well as a fold-down armrest, those USB ports and rear temperature control (but curiously, no fan control). The seats are comfortable enough, but space is limited. Realistically, it’s best suited for two passengers, not three.

Boot space is quite practical. The wide opening and manageable load lip height make it easy to slide items in and out. It offers 325L of space, less than its key rivals, but expands to 1145L with the rear seats folded flat. The handy 40/20/40 split also adds versatility. Under the boot floor, you’ll find a tyre repair kit.

The A3 Sportback comes in three trim levels, with the S3 technically sitting in the middle, just below the performance-focused RS 3. It's priced from $78,800, before on-road costs, and it shares the same platform and underpinnings as the Volkswagen Golf R. Surprisingly, our test vehicle isn’t significantly more expensive than its Golf R rival which comes in at $70,990 MSRP.

That makes it a more affordable option when compared to premium rivals like the BMW M135 xDrive which starts at $83,600 MSRP and the Mercedes-AMG A35 which comes in at $89,700 MSRP.

The update sees engine outputs improve with it gaining 17kW and 20Nm of torque, resulting in a total of 245kW and 420Nm.

Feature highlights include 19-inch alloy wheels, red brake calipers, electrically-adjustable and heated front seats (with expandable under-thigh support), rear privacy glass, quilted Nappa leather upholstery and 'S Sport' suspension with damper control which lowers the ride height lowered by 15mm.

The updated technology is well-rounded and now comes with wireless Apple CarPlay and Android Auto. There's also three-zone climate control, a 10.1-inch touchscreen multimedia display, a 12.3-inch digital instrument cluster, digital radio, four USB-C ports, a wireless charging pad, built-in satellite navigation and a 15-speaker Sonos 3D sound system.

Still, despite its premium hot hatch status, this grade skips a few luxury touches. Ventilated front seats, a heated steering wheel, heated rear outboard seats and a sunroof are all missing. The BMW M135 xDrive, notably, includes all of these as standard.

Even the powered tailgate with kick-functionality is an optional extra here, adding $660 to the price. At this level that should be standard.

Probably the biggest departure compared to any previous C-Class is this generation's switch to direct-injection four-cylinder-only powertrains – including the coming Mercedes-AMG high-performance versions. Now that should be interesting.

As mentioned earlier, the C200's four-cylinder turbo engine is now about 25 per cent smaller in capacity, down from 2.0L to a 1496cc 1.5L twin-cam 16-valve turbo engine. Dubbed the M254, it pumps out 150kW of power at a high 6100rpm and 300Nm of torque between 1800-4000rpm.

That's not to say it's lacking in muscle, though, since it can sprint from zero to 100km/h in 7.3 seconds, on the way to a 245km/h top speed. These outputs are at least a match for the bigger-engined 3 Series and A4 equivalents, by the way.

If it's more you want, then the C300 features a 1999cc 2.0L turbo version of the M254, delivering 190kW at 5800rpm and 400Nm between 2000-3200rpm. This slashes that 0-100km/h time to a speedy six seconds flat. There's also an extra 20kW of overboost available for short periods if you're really in a hurry, while - where legal - it's possible to hit 250km/h.

Both send drive to the rear wheels via a nine-speed torque-converter automatic transmission, while the 48V mild-hybrid system, dubbed EQ Boost, employs an integrated starter-generator and lithium-ion battery that provides an additional 15kW and 200Nm of electric boost at low engine speeds.

So, while it doesn't ever run purely on electricity, the electrification tech certainly either brings more punch or takes the load off the petrol engine, depending on how you're driving it.

The S3 Sportback wears the quattro badge proudly, meaning it’s all-wheel drive and it pairs a tweaked seven-speed automatic transmission with a 2.0-litre turbocharged, four-cylinder petrol engine.

This update brings a bump in performance over the previous model, including the addition of a rear torque splitter. Power is now up to a gutsy 245kW and 420Nm of torque, launching the S3 from 0 - 100km/h in just 4.7 seconds. That’s proper hot hatch territory.

Remember when I said that the C-Class moved to an all-four-cylinder engine range? Well, that's primarily to help it better meet fuel consumption, efficiency and lower emission targets.

On the Australian combined fuel consumption cycle, the C200 manages 6.9 litres per 100km – and that's extremely impressive for a medium-sized sedan weighing almost 1.8 tonnes. So is the fact that the larger-engined C300 returns only 0.4L/100km more at 7.3L/100km. Fitted with a 66-litre tank, these numbers suggest that the former can average nearly 960km between refills while the latter can manage just over 900km.

These figures translate to averages of 157 and 164 grams per kilometre of carbon dioxide emissions respectively. On the flipside, both these Euro-6 emissions rated engines require 98 RON premium unleaded petrol to deliver their best.

So much for lab tests. Out in the real world, we drove both cars for several hundred kilometres on a hot summer's day, from inner Melbourne during peak-hour traffic, to some great curvy rounds out in central Victoria, featuring some tight corners and ample opportunity to really stretch both cars' legs.

Over these routes, we averaged an indicated 8.4L/100km in the C200 and – astonishingly – 7.4L/100km in the C300. Yes, the larger and more powerful engine proved more economical.

Clearly, along with the advanced aerodynamics, engine stop/start system and 48V mild-hybrid tech, all that downsizing works. No wonder Mercedes deemed it unnecessary to bother with diesel engines for this generation C-Class.

The S3 Sportback has an official combined fuel consumption figure of 7.9L/100km and a 55-litre fuel tank, giving it a theoretical driving range of up to 696km.

Its key rivals hover around similar numbers, so it's right on the mark for the segment. After a mix of long-distance drives and my usual urban errands, my real-world figure came in at 8.0L/100km - very close to the claim, which I’m pretty happy with.

There has been a philosophical shift in how the C-Class is presented.

Even with their standard-in-Australia AMG Line package, the regular grades like the C200 and C300 are now leaning into the brand's luxury heritage, while the BMW-baiting sports sedan versions will be left to the coming AMG versions.

And this in turn profoundly informs how the W206 drives.

Even with the optional Sports Pack on 19-inch wheels, the C200 as tested finally feels like a premium midsized sedan experience. Muted at start up, the 150kW/300Nm 1.5L turbo steps off the line smartly and smoothly, its nine-speed auto shifting effortlessly through the gears to keep the engine feeling lively and lusty.

Around town it's easy to mistake the engine as a larger-capacity unit, since throttle response is instantaneous, with little to no lag detectable. It's a strong start for a base powertrain, especially as the C200 settles into a relaxed cruise at freeway speeds. Cycling through the driving settings also reveals how feisty the 'Sport' mode is.

But the 1.5L's lack of size becomes obvious the moment you need to overtake quickly, or when a quick squirt of acceleration up a hill is required, because the engine needs plenty of revs to approach that 6100rpm power peak. While still pretty brisk in these situations, it's also fairly vocal too, with a sense of having to work hard to maintain momentum.

Switching to the C300 highlights how much better suited the 190kW/400Nm 2.0L turbo is to highway driving, leaping forward with much more force and conviction, across the entire performance spectrum. In every metric, this is a better choice – throttle response, mechanical refinement, cruising ease. And the fact that the onboard computer showed less fuel consumption cements our preference for the larger-hearted C-Class.

In fact, both models possess a chassis that feels like it could do with a whole lot more power. Light and tight around town, the steering weighs up nicely at higher speeds, with a linear and reassuringly planted feel. The same also applies to how confident and controlled the Mercedes feels through fast, tight turns, yet settles into a relaxed and comfortable tourer along long, straight stretches of road.

It's a pity, then, that such dynamic agility and prowess doesn't really involve the driver, since the steering feels quite isolated from what's going on underneath; for the vast majority of C-Class buyers, that's fine. But, as a quick spin in any latest BMW 3 Series or Jaguar XE will reveal, there isn't an intimate, two-way connection going on here. That's probably going to be reserved for the AMG models.

Our C200 rode on bigger wheels and steel springs, while the C300 was fitted with optional adaptive dampers. In the previous-generation C-Class, the differences would be stark: a busy and jittery ride in the former, compared to soft yet still unsettled suspension in the latter.

That's all ancient history now, as even the 'passively' suspended C200 now isolates its occupants from the rough and tumble of our inconsistent roads. Still firmish, but no longer harsh.

And the C300 with adaptive dampers seems downright plush by comparison, while offering the driver personalisation options within the aforementioned driving models to tailor the steering, performance and engine sound settings that best suit the prevailing mood.

Too bad there's some road and tyre noise intrusion heard inside when driving over coarse bitumen roads. This is a common pitfall amongst German vehicles in Australia.

Still, it doesn't detract from the fact that the whole chassis set-up can at-last cushion and cosset occupants like, well, a mini S-Class.

Which is the whole point of the W206 C-Class. It now majors on comfort and reassurance like the better Mercedes-Benz models used to, while still being suave and sprightly enough to be a memorable – if not over-exciting – drive.

As a result, the C300 especially is a much-more likeable car than past iterations. Just remember to tick the adaptive damper option for the most optimal experience. Job well done, Mercedes.

The S3 Sportback sounds as mean as it looks, and it delivers on that promise with effortless grunt. Acceleration is immediate, with plenty of power on tap when you need it. It’s just fun all around.

The lowered sports suspension and wide tyres do bring some extra noise into the cabin, even at lower speeds. You might find yourself repeating things to rear passengers now and then, but it never feels overwhelming.

Steering and suspension are on the firmer side, so yes, you’ll feel the bumps but the payoff is sharp, responsive handling. Quick lane changes and winding coastal roads are where this car shines.

Visibility is about what you’d expect from a low-slung hot hatch. The pillars don’t obstruct the view, but sitting beside a towering SUV at the lights can make you feel a bit... compact.

Cornering is a strong suit, thanks to the car’s wide stance and AWD system. It feels confidently planted in most conditions. That said, I noticed the occasional wobble through the rear frame on rough sections in heavy rain.

Its compact size makes parking a breeze, especially with the help of multiple sensors. The reversing camera is crisp, but at this price point, the lack of a 360-degree camera view feels like a missed opportunity.

The S3 isn’t covered by its 2WD sibling's maximum five-star ANCAP safety rating but it is well-equipped with safety features all the same.

Safety equipment includes blind-spot monitoring, side exit assist, rear cross-traffic alert, lane departure alert, lane keeping aid, park assist, reversing camera, front/rear parking sensors, forward collision warning, autonomous emergency braking and adaptive cruise control with stop and go function. 

It also has six airbags but misses out on a front centre airbag. None of the driver assist systems are intrusive to daily driving, which I always like.

The rear row has ISOFIX child seat mounts and three top-tether anchor points but only two child seats will fit.

Kudos to Mercedes-Benz for being the first luxury manufacturer in Australia to offer a five-year/unlimited kilometre warranty – matching most other mainstream makers. Lexus and Audi have only recently followed suit.

A five-year roadside assistance subscription is also included. Service intervals are 12-monthly or at every 25,000km, whichever occur first.

Additionally, a four-year capped price service plan is available, at $550 for the first year, $900 for the second, $1000 for the third and $2450 for the fourth, totalling $4900.

Alternatively, buyers can also choose three pre-purchase service plans to save a bit of money, but these must be bought prior to the first service.

Audi backs the S3 Sportback with a five-year/unlimited kilometre warranty, which is on par with its European rivals. A five-year pre-paid servicing plan is available for $2890 which is cheaper than pay-as-you-go and reasonable for the class.

For those looking to go the extra mile, the 'Audi Advantage' package lets you extend the warranty and capped-price servicing by an additional two years, which represents solid value overall.

Servicing intervals are every 12 months or 15,000km, whichever comes first.