Audi RS Q3 vs Mercedes-Benz C350 E

What's the difference?

The Audi RS Q3 Sportback edition 10 years is dynamically brilliant, beautifully finished and surprisingly civilised on day-to-day duty. A polished compact performance package that even in this special 'get-it-while-you-can' guise offers compelling value relative to its direct competitors.

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.

There's a lot going on with the RS Q3's exterior design; a mix of jagged lights, hard character lines, broad haunches and multiple vents surrounding the brand's signature, six-sided grille up front.

The big 21-inch rims fill the arches nicely and the rear features a deep diffuser with fat exhaust finishers poking out either side.

It's a purposeful, macho look and the Sportback edition 10 years is defined by a black package which adds gloss black to the side window trim, front spoiler blade, side blades, rear diffuser and exterior mirrors.

The limited edition is available in two colours, 'Chronos Grey metallic', which is unique to this model and 'Dew Silver matte' which will now be added to the broader RS Q3 colour palette.

Premium performance feels like the dominant theme inside with a typically Audi tech-focused approach including high-quality brushed metal elements, matt carbon inserts and quilted leather trim on the heavily bolstered front seats.

A meticulous attention to detail is obvious and the bottom line is it's all about the driver. A grippy, flat-bottom, leather-trimmed steering wheel looks as good as it feels, sleek screens enhance the racy vibe and the mix of physical and digital controls is sensible.

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.

Snug but spacious enough, the RS Q3 Sportback's driver and front passenger are provided with plenty of breathing room without upsetting the intimate, performance car feel. Just be prepared for a bit of head-ducking physical origami when folding yourself into either of the heavily bolstered front seats.

Storage includes door bins with room for bottles, two generous cupholders in the centre console, a lidded tray in front of the gearshift (which doubles as the wireless device charging bay), a storage compartment and owners manual holder under the front seats, a modest glove box and an adjustable front centre armrest with storage compartment.

Given this car measures just over 4.5m end-to-end, a close to 2.7m wheelbase is significant  and rear room is generous given the Q3's overall footprint. Plenty of head and legroom (for me at 183cm) with enough width for three adults on short journeys. A trio of up to teenage kids will be fine.

The back seat is able to slide for extra legroom (and slightly less boot space), while backrest angle is also adjustable.

Storage runs to small bins in the doors, a fold-down centre armrest (with two pop-up cupholders) and storage nets on the back of the front seats. Directional and temperature control in the rear for the ventilation system is a big plus.

Power and connectivity options run to a 12V outlet and two USB sockets in the front (Type A and C), another two Type C sockets in the back and a second 12-volt jack in the boot.

Speaking of which, cargo volume with all seats up is a handy 530 litres, enough to swallow CarsGuide's three-piece luggage set or large pram (the latter with room to spare) and 1400 litres with the 40/20/40 split-folding rear seat lowered.

The loading lip is low, a stainless steel sill protector helps minimise scuffs and scratches and the hands-free power tailgate is welcome.

If you're keen to hook up the boat or horse float the RS Q3 is able to tow a braked trailer up to 1900kg (750kg unbraked), but don't bother looking for a spare of any description, a repair/inflator kit is your only option. Boo...

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 Q3 Sportback is powered by a 2.5-litre in-line five-cylinder intercooled turbo-petrol engine sending drive to all four wheels via a seven-speed dual-clutch automatic transmission and Audi's quattro permanent all-wheel drive system based on an electronically-controlled multi-plate clutch pack.

Featuring a cast iron block, alloy head, direct-injection as well as variable intake and exhaust cam adjustment, the (EA855) engine features a special firing order (1-2-4-5-3), the odd number of cylinders producing a signature engine sound and exhaust note reminiscent of the 1980s 'Ur' Quattro.

Peak power is 294kW from 5850-7000rpm and maximum torque is 480Nm delivered across a broad plateau from 1950-5850rpm.

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.

Audi's official fuel economy number for the RS Q3 on the combined cycle is 8.9L/100km, the 2.5-litre turbo-petrol five-cylinder engine emitting 204g/km of CO2 in the process. Stop-start is standard.

We covered city, suburban and some freeway running on test, returning an (indicated) average of 9.6L/100km. And that's pretty good, given we pushed on enthusiastically on a reasonably regular basis.

The fuel tank requires 63 litres of 98 RON premium unleaded to fill it which translates to a theoretical range of just over 700km, shrinking to around 650km based on our real-world number.

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.

It still seems counterintuitive when a high-riding SUV is tuned to perform and handle like a low-slung sports car but here we are. And Audi executes this mystifying transformation as expertly as any carmaker in the automotive world.

Audi says the RS Q3 Sportback will blast from 0-100km/h in 4.5 seconds. Anything under 5.0 seconds is properly fast, and there's nothing quite like the deep-throated bellow of a VW Group in-line five to raise the hairs on the back of your neck.

The RS Q3's sport exhaust system is a dual-branch set-up with exhaust flap control, and people of a certain age will instantly imagine themselves matching it with Ari Vatanen, Walter Röhrl and Michèle Mouton on a suburban special stage behind the wheel of a 1980s Group B Sport Quattro rally car (actually, the school drop off at an infinitely more sensible pace).

The car weighs in at a not insubstantial 1775kg, but 480Nm, available all the way from 1950rpm to 5850rpm, means a near instant surge of fierce acceleration is always lurking under your right foot.

And the VW Group is on the pace when it comes to dual-clutch auto transmissions, from Porsche's 'PDK' and VW's 'DSG' to Lambo's 'DCT' and Audi's 'S tronic'.

The RS Q3's seven-speed unit is quick and positive, the wheel-mounted paddles ramping up the engagement factor.

The variable ratio, electrically-assisted steering is capital G Great. Well weighted and precise with reassuring road feel and the Alcantara trimmed wheel is a nice way to access it all.

Suspension is by struts at the front and multi-links (four) at the rear with adaptive dampers on-board.

Despite running on 21-inch rims, shod with high-performance 255/35 Continental PremiumContact 6 rubber, ride comfort is surprisingly good.

Dial in 'Comfort' mode via the 'Drive Select' system and the impact of even substantial bumps is softened off appreciably.

An ideal set-up would be the first 'RS1' short-cut Drive Select button set for Comfort suspension, with throttle, steering and transmission set to maximum attack and the second 'RS2' mode tweaking the suspension to track-day level, too.

Push on through your favourite set of bends and you can feel the electronic wheel-selective torque control system keeping everything under control. This car puts its power down through sweeping sections with fuss-free authority.

The RS-specific menu in the digital instrument cluster provides extra instrumentation in the shape of a power/torque display, G meter and lap timer. Fun!

The brakes are professional grade with big ventilated rotors all around and aluminium fixed calipers at the front.

But beware, the flip side of the RS Q3's quick steering response is a sizeable 11.8m turning circle. Take your time when parking.

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 Australia covers all the models it sells with a five-year/unlimited km warranty with 24-hour roadside assistance included for the duration. Pretty much cost-of-entry in this part of the market.

Paintwork defects are also covered for five years, and the body is warranted against corrosion (to the point of perforation) for no less than 12 years. Nice.

Service intervals are 12 months/15,000km and capped-price servicing is available, a five-year/75,000km plan for the RS Q3 costing $3580, an annual average of $770. Fairly steep.

An 'Audi Advantage' package is also available, adding an extra two years' worth of warranty, scheduled servicing and roadside assistance (to the end of any existing term) for $3800.

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.