Audi RS7 vs Mercedes-Benz C350 E

What's the difference?

The new-generation RS 7 Sportback heralds the further evolution of this large majestic beast, with more features, a beautifully finished cabin and with more grunt with the looks to match. You’d be hard-pressed to find a better combination of power, dynamics and comfort in the Audi range – apart from in the RS 6 Avant of course.

Plug-in hybrids will probably not appeal to all buyers, but in the premium space they make sense.

Smooth electric driving paired with the potential for weekend trips outside the 100km-or-so range make the C350e a decent thing, let alone its price parity with the C300.

It still doesn’t top the charts for value or practicality, but even aside from the PHEV tech, the C350e remains a fun-to-drive sedan that holds its own in the executive space.

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

The big news is the RS 7 Sportback now comes with five seats. The previous generation car had just two seats in the second row. I'll talk more on practicality below but for now let's examine the new styling.

This RS 7 Sportback has new broad, black mesh grille, flanked by gigantic side air intakes, narrow headlights, and a thin upper air inlet which is a hat tip to early racing Audis.

While that new angrier, more angular and menacing face is a showstopper, everything about the new RS 7 Sportback seems to be accentuated further.

Look at the wheels. The previous generation came with 21-inch rims, now the new normal for the RS 7 are 22-inches – they're huge. Those wheel guards also flare out 20mm more than a regular A7's and the rear haunches have bulked up massively.

Come to the back of the car and the diffuser and bumper have also been beefed up. Nobody sitting behind you in traffic is going to think this is just a regular A7.

Don't expect the RS 7 Sportback's insides to be just as hardcore as its exterior. The cabin is almost identical to a regular A7's. It's a stunning cockpit dominated by a dash which protrudes back towards the passengers and houses the media screen. Anther display for climate is set into the big centre console which divides the driver and co-pilot into almost cocooned cells.

The cabin isn't without its RS touches though – there's the sports seats with honeycomb stitching, fully digital instrument cluster with RS specific meters, the RS steering wheel, the Nappa leather on the dashboard and the doors, the aluminium inlays. The level of fit and finish is up there with the best that I've seen on any production car.

The RS 7 Avant is 5009mm long, 1424mm tall and 1950mm across for a wide planted stance.

The C350e doesn’t depart massively from the familiar visual formula that is the current ‘206’ generation C-Class and that’s no bad thing.

Call it conservative if you like, but having seen what’s possible when Mercedes takes risks (hello EQ models), the traditional Mercedes design language is put into healthy perspective. 

Handsome proportions and lines without any fuss - there are no unnecessary creases or panels or materials.

The plug-in C350e comes, as mentioned, with the AMG Line pack, adding 18-inch five-spoke AMG wheels, an AMG front apron, grille insert, and of course EQ Hybrid badging.

The pack also includes AMG Line styling inside, where you’d have to be a Mercedes regular to spot the specifics. The AMG-style steering wheel and seats are the biggest giveaways.

The previous RS 7 Sportback was a four-seater, now it has five seats. That's right, a middle seat has been added to the second row, but, as you'd expect, it's not the best place be in the RS 7 Sportback, straddling the large driveshaft and ducking under the low roof-line.

That fastback profile does mean headroom in the second row is nowhere near as good as the RS 6 Avant's, but legroom is the same and, at 191cm tall, I can just fit behind my driving position with about 10mm to spare.

Up front it's not as spacious as you might think. That stepped dash protrudes into the passenger's space, the door pockets are thin and the centre console storage under the armrest is small.

Sportbacks are more practical sedans thanks the large opening offered by the hatch. The boot's 535-litre cargo capacity is great and only about 30 litres less than what you have in the RS 6 Avant.

For phones there's a wireless charger and two USB ports in the centre console storage box, while back seat passengers have two USB ports and a 12V outlets. There's also directional air vents and dual-zone climate control in the rear, too.

The space inside the C-Class remains straight-forward as ever. The layout and features don’t stray from convention, meaning there’s a sizable central screen, digital driver display, central cupholders, and places to put things like a phone, with wireless charging included.

The electrically adjustable seat and steering column make getting into a comfortable position easy, and the memory settings keep it that way.

While physical buttons are scarce, the key controls are easy to access via the central multimedia touchscreen and there’s a lack of complicated sub-menus. It's a refreshingly straightforward system compared to some from rivals, especially that of former category benchmark BMW.

There are fewer than a dozen main tile buttons on the menu, and they’re clear and easy to work out. The main screen also defaults to the navigation, and the climate controls are always visible on the touchscreen.

The central storage area is laid out so a phone sitting in the charging pad is slightly hidden, meaning it’s not a distraction, plus the cover means the cupholders and storage can be hidden away. Tidy!

The AMG-style steering wheel’s haptic controls can be used as regular buttons, but more than once on the test drive I nudged the volume and turned my music back on, just a minor annoyance.

In the second row, there’s generous space for a mid-size sedan, and the seats are comfortable for an adult to ride along for a lengthy trip.

There’s a centre armrest, hidden cupholders, and a generally light and open feeling thanks to the panoramic sunroof.

The battery for the hybrid system sits under the second row seats, which means there’s no uneven flooring in the 315L boot.

The Mercedes-Benz C350e kicks off from $98,200, that’s before options and on-road costs.

And there are some key options, the main one being the ability to DC fast-charge which costs $1500 and brings the total to $99,700.

Pricing sits par with the C300 non-PHEV because of its similar specification, and Mercedes Australia said it wanted to give buyers the choice of internal combustion engine (ICE) or PHEV without having to consider the costs.

There’s a decent stack of standard kit in the C350e, including power adjustable heated leather seats, a 12.3-inch multimedia touchscreen and same-size digital driver display, head-up display, and wireless Android Auto and Apple CarPlay.

The C350e also scores some more fun stuff as standard, including a Burmester surround sound system, panoramic sunroof, the Driving Assist Plus pack, augmented reality MBUX, and the AMG Line pack which adds some sportier-looking design features.

It also comes with Mercedes’ Comfort Suspension which includes self-levelling suspension, and Digital Lights with adaptive high beam.

The RS 7 may look like a large, well-mannered business class car, but think of it as a thug in a suit because this thing is a monster with a 441kW/800Nm twin-turbo petrol 4.0-litre V8.

That's almost 600 horsepower and the supercar acceleration that goes with it is brutal: we're talking 0-100km/h coming in 3.6 seconds. That also matches the RS 6 Avant and it's a tenth of a second faster than the Audi R8 V10 RWD supercar, (and also the previous-gen RS 7 Sportback Performance) and this is a large, four-door, five-seater.

Compared to the previous generation RS 7 Sportback Performance the power is down by 4kW, but torque is up by a whopping 100Nm. Give me torque over power any day.

Shifting gears is an eight-speed automatic transmission, sending the drive to all four wheels.

The C350e’s plug-in hybrid drivetrain consists of a 2.0-litre turbo-petrol four-cylinder engine and an electric motor that drives the rear wheels via a nine-speed automatic transmission.

The combustion engine’s peak outputs are 150kW and 320Nm, while the 95kW/440Nm electric motor works with it to land on a total system output of 230kW and 550Nm.

While it’s not lightning quick, the C350e has a decent claimed 0-100km/h sprint of 6.1 seconds, and from the driver’s seat it certainly feels brisk enough to get out of its own way.

This is a large, all-wheel drive car with a 600 horsepower V8, but it also has a mild hybrid system in this new generation, which will switch the engine off at let the car coast down hills or at speeds under 22km/h.

Audi says this can save up to 0.8L/100km in real-life driving. That's great news, but consumption is still fairly high with Audi saying that after a combination of open and urban roads the RS 7 Sportback will have used 11.6L/100km.

Mercedes officially claims the C350e has a driving range of 104km under NEDC testing, with a 25.4kWh battery supplying the juice.

Official fuel use is just 1.5L/100km, but Mercedes says that becomes 7.6L without any battery charge to help it out.

Under standard 11kW AC charging, it’s about two hours from flat to full, but with the optional 55kW DC fast-charging, it takes about 20 minutes from flat to 80 per cent.

I've never met an RS model that hasn't been great to drive – these cars are way more than just tough body kits and big wheels. The engineering which separates the RS 7 Sportback from the A7 makes them more distant cousins than siblings.

As I mentioned before the RS 7 Sportback and RS 6 share more than the same twin-turbo V8, there are also the giant brakes in form of 420mm discs at the front with 10 piston calipers and 370mm discs at the rear.

The optional carbon ceramic brakes are the largest ever to be fitted to a production vehicle at 440mm at the front and 370mm at the rear, saving 34kg in mass over the steel brakes.

Now standard for the first time is Audi's Dynamic Package, which adds dynamic steering (a variable ratio) paired with all-wheel steering, a sport differential, and a 280km/h top speed.

Coming standard is adaptive air suspension and for $2850 you can option the Dynamic Ride Control suspension, which is a hydraulically activated adaptive damper system 

At the Australian launch, Audi supplied two RS 7 Sportbacks: one with the air suspension and the other with not only the Dynamic Ride Control system, but also the RS Dynamic Package Plus which adds the ceramic brakes and increases the top speed to 305km/h – this was the car I started off in.

I'm going to say right away that you don't need ceramic brakes for regular road use. Sure it means you can tell people that you have the biggest brakes in the world and they save you almost 35 kilos in weight, and, yes, they're resistant to fading, but they're expensive to replace and the steel ones are incredibly good.

I also feel the Dynamic Ride Control sports suspension isn't necessary in a car like the RS 7 Sportback. This is a Grand Tourer designed to eat up hundreds of miles at lightspeed in comfort.

So, while I found the first RS 7 Sportback with the big brakes and sports suspension sharper and firmer than the standard car, it didn't seem to fit with this vehicle's intent.

The regular RS 7 Sportback still accelerated with the same brutal force and roared at the scenery flashing past. It still handled through the tight corners superbly with excellent turn in, mind-boggling traction and grip, and excellent body control, but all in far more comfort.

This is the point – we covered hundreds of miles at the Australian launch of the RS 7 Sportback in a range of RS models, and sports suspension can go from great to gruelling on Aussie roads with their coarse-chip bitumen and potholes. The RS 7 Sportback, with its air suspension, not only made driving far more comfortable, but easier, too.

The C350e has a few drive modes that are mostly self-explanatory, those being Battery Hold, Electric, Hybrid, Sport and Individual.

You’ll likely find yourself using Electric and Hybrid most of the time, so we’ll focus on those. Sport is fine but somewhat defeats the purpose of the plug-in system for day-to-day driving.

In electric mode, the C350e doesn’t feel like it’s lacking any power without the engine helping it along. Acceleration is smooth, brisk enough, and a 130km/h top speed means you won’t need the engine on your commute.

Realistically, its 104km range is probably somewhere closer to 80km, but covers you for a decent daily distance.

Let the car use the engine to help out via Hybrid mode and, if you’ve got music playing, you might not notice the engine starting and cutting. The system is smooth and it means a much longer life out of the battery before needing to charge. That, and there’s the benefit of more brisk acceleration thanks to the hefty 230kW/550Nm total outputs.

Everything else about the C350e is classic C-Class - the ride is controlled and the suspension does a decent job of soaking up bumps and rough roads, the comfort and self-levelling suspension makes cornering smooth and inspires confidence.

The most noticeable shortcoming for the car is its transmission hesitation if you put your foot down quickly, though the ability to use the paddles to choose your own gears in Sport mode avoids this.

In Electric or Hybrid, the paddles decide how much braking regen to apply, a useful feature that lets you recuperate some power for the battery if your drive includes a lot of downhill slopes or if you’re avoiding relying on the brake pedal.

The C530e’s extra weight doesn’t dull its driving characteristics as you might expect from a car laden with PHEV tech, so it’s a welcome surprise that you could pick up a plush plug-in for the same price as a combustion C300.

The C-Class has a five-star ANCAP rating, but it was tested in 2022 before the plug-in variant arrived.

Still, 10 airbags and an advanced list of safety features provides peace of mind.

The C-Class benefits from the brand’s Pre-Safe collision protection system to minimise occupant injuries from an impact, even to your hearing.

It also has emergency collision avoidance via steering input, driver monitoring, speed limit assist with adaptive cruise control, and parking sensors with surround-view cameras.

The RS 7 Sportback 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 with a three-year plan costing $2380 and a five-year plan for $3910.

Mercedes has a five-year, unlimited kilometre warranty which is decent for a premium brand.

Servicing is pricey, though. 

A three-year pack covering a service every 12 months (or 25,000km, whichever comes first) costs $3355, that being just three services.

Four years costs $4630, or five includes a more expensive service and brings the total to $6890. That’s an average of $1378 per service.

Finding somewhere to spend that money shouldn’t be hard as there are 100 dealers listed in Australia.