Audi RS5 vs Mercedes-Benz C350 E

What's the difference?

Good looking, good to drive, and good to simply sit in, the Audi RS5 range ticks plenty of premium boxes. Whether you can live with the practicality pitfalls of the Coupe is up to you, but if you can't, might I suggest taking a wander over to our RS4 Avant review?

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.

I defy anyone to describe the RS5, and especially the Coupe, as anything but stunning. Seriously, the near perfect proportions and swept-back styling make it look fast even when it's parked. 

Up front, there's a new-look black-mesh grille that's been given a 3D effect, like it juts out over the road in front it, while the thing headlights have been carved back into the body work like they're been windswept under hard acceleration.

The 20-inch darkened alloys fill the arches, too, with a sharp body crease that runs from the front headlight all the way back to the bulging shoulder lines above the rear tyres accentuating the curves.

Inside, the RS5 is a sea of black Nappa leather and sporty touches, and we particularly like the chunky, flat-bottomed steering wheel, which both looks - and feels - great.

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.

We only tested the Coupe, and I can tell you that the practicality perks on offer largely depend on where you're sitting.

Up front, you're spoiled for room in the two-door Coupe, with the two spacious seats separated by a sizeable centre console that's also home to two cupholders and a variety of cubbies, with extra bottle storage in each of the front doors. 

The back seat, though, is a little, or a lot, tighter, with come acrobatics required to even climb into it, given the Coupe only has two doors. The Sportback offers two more doors, which will surely make the process a little easier. 

The Coupe measures 4723mm in length, 1866mm in width and 1372mm in height, and will deliver a decent 410 litres in luggage space in the boot. The Sportback measures in at 4783mm, 1866mm and 1399mm, and boosts your luggage space to 465 litres.

Either vehicle has your tech needs sorted, with an abundance of USB and power outlets serving both front and backseat riders.

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.

Its a terrific engine, this - a twin-turbo 2.9-litre six-cylinder TFSI that will deliver 331kW at 5700rpm and 600Nm at 1900rpm, sending it thundering to all four wheels (because quattro) via an eight-speed tiptronic automatic.

That's enough, says Audi, to deliver a 0-100km/h sprint time of 3.9 seconds in the Coupe and the Sportback. Which is very, very quick.

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.

The RS5 Coupe will sip a claimed 9.4L/100km on the combined cycle, and emit a claimed 208g/km of Co2. It's fitted with a 58-litre fuel tank. 

The RS5 Coupe will the same 9.4L/100km, but emit 209g/km of Co2.

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.

With our time behind the wheel limited to the RS5 Coupe, we can only really report on how the two-door feels on the road, but given the prodigious power on offer, it's unlikely the addition of two doors is going to make the Sportback any slower. 

In short, the RS5 is thunderously fast, collecting speed with utter nonchalance thanks to this thick and endless-feeling supply of power unleashed whenever you plant your right foot.

It makes even the most ham-fisted attempts at cornering feel fast as lightning, with the power flow able to make up for every slow entry and exit by simply piling on pace between bends. 

But that's what you expect from an RS model, right? So perhaps more impressive is the RS5's ability to transform back into a relatively sedate urban cruiser when the red mist subsides. The suspension is firm, especially over rough road surfaces, and you do need to be a little careful with the accelerator to avoid that lurching feeling at every green light, but driven calmly, it doubles as a everyday car quite nicely.

Like in the RS4, we did find the gearbox felt a little quick to change at pace, shifting up or down at strange moments on the way into or out of corners, but you can reclaim control via the paddle shifters.

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.

Audi vehicles are covered by a three-year, unlimited-kilometre warranty, which is feeling more than a little underdone when compared to some competitors.

Services are due every 12 months or 15,000kms, and Audi allows you to pre-pay your service costs for the first five years, at a cost of $3,050.

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.