BMW I3 vs Mercedes-Benz C350 E

What's the difference?

Yes, it’s pricey for a small hatch, but this little BMW is a city car like no other. The i3s is tailor made for the urban environment, and six years on retains the quirkiness and charisma that stood it apart at launch, and it can still hold its head high among the current EV crop. 

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.

Built around a carbon-fibre reinforced plastic (CFRP) tub, the i3s is ultra-light (for a battery-electric vehicle), super strong, and unlike anything else on the road.

At just over 4.0m long, close to 1.8m wide, and a fraction under 1.6m tall, the i3s is compact, upright, and boxy. A classically polarising design, with some crossing the street to avoid it, and others (like me) loving its unique proportions and stand-out styling.

The nose is tall, short and upright, with the distance from the base of the front windscreen to the front axle (car designers call it the ‘dash-to-axle ratio’) unusually short.

That’s because the electric motor sits in the back of the car driving the rear wheels, with only a small front boot compartment required to house charging cables and other bits and pieces.

Despite the lack of anything of substance behind it, BMW’s signature ‘kidney grille’ is present and accounted for, with swoopy LED headlights (and DRLs) either side. Our test car’s ‘Fluid Black’ finish with ‘i Blue’ highlights dialed up the little car’s charismatic personality.  

One of the i3’s most impressive party tricks is its counter-opening ‘clamshell’ doors, and the engineering trickery used to create a B-pillar free side opening (including the strength of the carbon body structure) means the high window line follows a jagged path from front to back, the rearmost hatch windows shrinking the rear glass area appreciably.

The i3s’s standard 20-inch (dual) five-spoke alloy rims, although slightly wider in this performance model, are alarmingly skinny. But taking the car’s relatively light weight (1245kg) and urban-centric purpose into consideration, the narrow, low-rolling resistance rubber makes sense.

With the roofline and sides of the car tapering distinctly towards the back, the rear view is suitably idiosyncratic, highlighted by flush-fit, vaguely U-shaped LED tail-lights. 

The hatch window is small, and the bumper sits high to marry with the load space floor sitting on top of the motor and transmission.

And when it comes to moving inside, BMW offers a choice of three ‘interior worlds - ‘Loft’, ‘Lodge’, and ‘Suite’ - featuring renewable natural fibres, recycled plastics, naturally tanned leather, and open-pore wood (sourced from 100 per cent Forest Stewardship Council-certified forestry).

But irrespective of where everything comes from, the end result is inviting, comfortable and sub-zero cool. Our car’s ‘Suite’ interior was combined with ‘Oak dark matt’ wood, and ‘Vernasca’ brown leather to stunning effect.

A tunnel-free floor, gently curved dash and digital screens for instruments and media let you know you’re in something different and special. It might be six years old, but the i3 still feels contemporary and distinctive. 

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.

Wide-opening clamshell doors make getting in and out of the i3s a breeze. But bear in mind you have to open the front door to get to the latch for the back one, which can be a pain.

The driver and front passenger enjoy heaps of room, in an open environment, but there’s only a single cupholder in the centre console, so let the coffee cup wars begin.

Aside from that there are seriously big bins in the front doors, a modest glove box, and a handy elasticised pocket near the floor at the base of the bulkhead.  

Outlets for 12-volt and USB are provided, and there’s a small oddments tray at the rear of the centre console.

Slip around to the rear and you’re in anything but limousine territory. Sitting behind the driver’s seat set for my 183cm height, head and legroom are modest but do-able. And remember it’s two seats only back there.

In terms of storage, there are two cupholders between the seats but no storage pockets or bottle holders in the doors. You won’t find adjustable ventilation outlets either, but that’s not a huge factor in car of this stature.

The boot’s volume is quoted at 260 litres with the 50/50 split-fold rear seatback upright, which is enough to easily swallow the largest 124-litre suitcase in the CarsGuide three-piece set. The smaller 95- and 36-litre cases will sit side-by-side without a problem.

Fold the rear seat down and you have 1100 litres of space at your disposal, with tie-down anchors, an elasticised pocket and 12-volt power provided.

Don’t bother looking for a spare of any description, a repair/inflator kit is your only option. And not surprisingly, the i3 is a no-tow zone. 

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 i3s is powered by BMW’s ‘eDrive’ hybrid synchronous electric motor, producing 135kW at 7000rpm, and 270Nm from 0-4500rpm. Yep, that’s right, maximum torque is delivered the instant you depress the right-hand pedal, and we’ll get to what that brings to the driving experience a little later.

The unit incorporates a charging and generator function for braking energy recuperation, the latter delivering up to 50kW.

Drive goes to the rear wheels via a single-speed (fixed-ratio) automatic transmission.

The battery powering the whole show is a 352-volt/120 amp-hour (Ah) Lithium-ion unit with a (gross) energy rating of 42.2kWh.

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.

When it comes to an electric car’s energy use and projected range, there are two main things to consider - the motor’s power consumption and the battery’s capacity.

And according to BMW, the i3s’s power consumption for the combined (urban/extra-urban) cycle is 14.6–14.0kWh/100km.

Over a week, and roughly 250km of urban driving (with some brief freeway runs thrown in) we saw 19.3kWh/100km staring back at us from the on-board computer.

When BMW launched the i3 in Australia in 2014, the pure EV version came with a 60Ah battery pack delivering a claimed 130 kilometre range (a range extender model featuring the addition of a two-cylinder petrol motorcycle engine was also offered). 

In 2016 a 94Ah version arrived to boost range up to 183km, and the i3s launched in 2018, with its 120Ah battery pushing range out to BMW’s current, real-world estimate of 260km.

Then, there’s charging time, which is like asking how long is an electric piece of string.

According to BMW, for a 0–80 per cent charge from a (50 kW DC) fast-charging station, you’re looking at 45min.

From a (11kW/16A/380V) high-output home/office wall unit, that pushes out to 3.10h, and using a (3.7kW/16A/240V) low-output home/office unit stretches the wait time to 9.40h.

BMW offers the ‘WallBox plus’ charging suite as a dealer accessory priced from $1990 (not including GST or install costs).

Plug into a domestic (2.4kW/10A/240V) socket, and you’re staring down the barrel of 15.00h. But at least you can use low-cost, off-peak energy overnight, right? Nah, I don’t buy that line either.

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 might not look like a conventional sports car, but the BMW i3s certainly accelerates like one, with a claimed 0-100km/h time of 6.9sec. The i3s is a smile-inducing hoot to drive.

Every one of this little hatch’s 270 newton metres of torque is available from the minute you hit the accelerator pedal, and remain in service until 4500rpm, at which point torque delivery drops off a cliff.

But peak power steps in at exactly 7000rpm, so if you’re determined to make that overtaking move you won’t be left in the lurch. In fact, BMW says it only takes the i3s 4.3 seconds to surge from 80km/h to 120km/h.

However, the i3’s forte is 100 per cent the city, rather than the open road. Its ‘point and squirt’ ability making it the perfect partner for the cut and thrust of the urban jungle.

The i3s features an upgraded ‘Sports Suspension’ incorporating firmer dampers, re-tuned springs and revised anti-roll bars. It’s also lowered 10mm, the track is widened (+21mm front / +2.0mm rear) and the wheels go plus one inch to 20-inch alloys.

The standard i3 (no longer offered in Australia) rolls on 19-inch rims shod with 155/70 rubber all around. And while the i3s’s 175/55 front and 190/50 rear tyres are still exceptionally narrow, from the side the low-profile Bridgestone Ecopias look like fan belts wrapped around pulleys rather than tyres around wheels..

No surprise then that ride comfort isn’t exactly cushy, and in signing on for the i3s experience you’ll need to be ready for more than occasional bumps and thumps.

But the pay-off is super-sharp dynamics, Suspension is by alloy struts at the front, and a five-link alloy set-up at the rear..The steering responds to inputs quickly yet smoothly, and with 48/52 front to rear weight distribution, the car always feels balanced, eager, and taut.

And if you really want to dial things up the ‘driving experience control’ allows a switch to Sport mode for a further tweak of the suspension, steering, and traction control set-ups.

A tight 10.3m turning circle makes for easy parking and stress-free U-turns. But if things get too tight, rapid three-point turns are assisted by the gear shift controller bring mounted on a chunky stalk on the right-hand side of the steering column. Too easy.   

Braking is by vented discs front and rear, but they’re tiny. That’s because the ‘Brake Energy Regeneration’ system does most of the work. 

Effectively turning the motor into a generator, the system not only slows the car dramatically but feeds energy to the battery in the process. It takes a while to get used to the sensation, but soon becomes a fun, and surprisingly easy game to use the brake pedal as little as possible… often not at all, for long periods.

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.

BMW offers a three year/unlimited km warranty, which is off the pace given the majority of mainstream brands have stepped up to five-year cover, with some at seven. And the pressure is on with Mercedes-Benz recently announcing its shift to five years/unlimited km.

That said, the BMW's body is warranted against rust (perforation) for 12 years/unlimited km, and roadside assistance is provided free-of-charge for three years/unlimited km.

Maintenance is 'condition based' with sensors and on-board algorithms (mileage, time since last service, driving style) determining whether an annual vehicle inspection is required.

The 'BMW Service Inclusive' package, offering a single, one-off advance payment to cover selected service and maintenance costs, is available in two levels - 'Basic' ($850) or 'Plus' (dealer quote)

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.