Mercedes-Benz C350 vs Mercedes-Benz E400

What's the difference?

Baby steps these might be, but they're important ones for Benz. The new in-cabin tech and clever engine in the cheapest models only strengthen the C-Class proposition, without taking anything away from the drive experience, cabin ambiance and utterly sublime ride.

In short, Mercedes' reign at the top of the premium mid-size segment is unlikely to be toppled anytime soon.

A convertible that doesn't feel like one when the roof is in place is no easy task to build, but it's one Merc's engineers have pulled off with the E400 4Matic Cabriolet. Effortless power, a tonne of technology and a comfy, leather-wrapped cabin all make Merc's drop-top E-Class a strong proposition.

Perhaps not quite blink and you’ll miss them, but we're not talking radical changes either, folks. Benz tells us as much as 50 per cent of the C-Class components are new or changed, but it has clearly subscribed to the 'if it ain’t broke' philosophy in the design department.

Yes, there are new bumpers front and rear, new LED light configurations and new colours and wheel designs, but we’re not talking huge changes outside. Still, the C-Class cuts a fine figure on the road, what with its intricate alloys, bonnet-defining grille and simple, understated body contours. Australia will take every available body style, too, including sedan, coupe, cabriolet and - our personal favourite - the 'estate' station wagon.

The C 43 AMG now gets the twin-blade grille design used on the V8-powered models, as well as a two pairs of rounded exhaust tips at the rear.

Inside, though, the changes are more substantial. For one, the new-generation Mercedes Touch Control steering wheel arrives as standard, as does a new and very effective 12.3-inch screen that replaces the traditional dials in the instrument cluster (standard on every model). 

The cabin remains a peaceful and premium-feeling space, with a fine use of materials (including quilted leather on the door panels, polished silver or faux-wood for the centre console and leather for the steering wheel), and Benz deserves credit for ensuring that sense of luxury extends to backseat riders. 

Elegance. That's the word that springs to mind when you first clamp eyes on the E400 Cabriolet. While the Coupe version has a crouched-over sportiness about its exterior design, the convertible is all about big and boat-like proportions, especially with the fabric roof opened.

Like nearly all drop-tops, the E400 looks best with the cabin open to the elements, and the side profile especially paints a picture of well-heeled wafting, with only the AMG alloys and body styling hinting at the performance on offer under the bonnet.

Inside, expect perfectly executed modern luxury, with soft leather seats, touchpoints that melt under the fingers and a sprinkling of woodgrain trim. All of which feel like old-world luxury, nicely juxtaposed by the huge twin-screen display that dominates the dash.

It all depends, really. All C-Class variants sit on the same 2840mm wheelbase, and stretch 1810mm in width. The sedan, coupe and cabriolet versions measure 4686mm in length, while the Estate’s bigger cargo area increases its size to 4702mm.

Predictably, then, the estate offers the most useable (VDA) boot space, with 490 litres with the rear seats in place, swelling to 1510 litres with the rear seats folded flat. The sedan version is next on the cargo-carrying list, with 455 litres, followed by the 380 litres of the coupe and 285 litres of the cabriolet.

We spent our entire time in the four-door sedan models, and we can report a spacious and comfortable space for driver and passenger (you could play ping pong on the wide centre console) with two cupholders and room in each of the front doors for bottles. There’s all the USB and power connections you might need (most housed in a deep storage bin that separates the front seats) and the more expensive models offer wireless charging for compatible phones, too.

Climb into the sedan’s back seat, and you’ll find impressive legroom (behind my own 176cm driving position), but headroom - especially in sunroof-equipped cars - feels a little tighter. The rear seat is actually wide enough to fit three adults at a pinch, but the tall and bulky tunnel absolutely obliterates leg room for the middle-seat rider.

There are two cupholders in the pulldown divider that separates the backseat, as well two ISOFIX attachment points. Rear occupants also get there own air vents, as well as a 12-volt power source.

It's a two-door, four-seat convertible, so practicality isn't at the very top of its list of strengths.

That said, life is peachy for upfront riders, both of whom will travel in spacious luxury. There are two cupholders hidden beneath a woodgrain cover underneath the climate controls - also home to a power outlet - as well as a clever double-hinged central storage bin that can be opened by either the passenger or driver, and which opens to reveal two USB points.

There's room in the doors for bottles, too, and the entertainment system can be controlled via a touchpad controller mounted above the traditional click wheel - although, to be honest, using it is harder and more time consuming than simply pretending it doesn't exist.

Climbing into the back (and we mean climb - there are no rear doors) is made easier by the fact you can fold and slide the front seats automatically by pulling a lever mounted near the headrest. Once there, though, you'll find space is a little tighter, and you feel weirdly cocooned, owing to the huge raised tunnel that runs through the middle of the cabin, and the low roof line.

There are two cupholders that live in the space where the middle seat would normally go, and there's a little bottle-holder cubby to the left of both backseat riders. There are air vents back there, too, but no temperature controls.

The front doors are huge and really very heavy, requiring considerable heft to open them.

The boot space is predictably a little limited, with 385 litres on offer. There's also a little flip-down separator, which shows you how much room the roof will need to come down, reducing boot space to 310 litres. Speaking of which, the soft-top can be lowered in just 20 seconds, and at speeds up to 50km/h.

One practicality quirk, though. The front (and only) doors are huge and really very heavy, requiring considerable heft to open them, especially if you're parked on a slight angle. Honestly, I was reduced to kind of pushing them open with my foot at times.

At $157,400, the Cabriolet is the most expensive model in the E400 family, and is roughly $20k more than the sedan and $10k more than the coupe variants.

That money buys you a comprehensively kitted-out ride - as it really should - with the E400 Cabriolet arriving with 20-inch AMG alloys, LED headlights (made up of 84 LEDs) with high-beam assist, proximity unlocking with push-button start, air suspension and Merc's AIRCAP - a lip above the windscreen that's designed to push air up and over the cabin when the roof is down.

Inside, you'll find leather seats, dual-zone climate control and the clever 'AirScarf' system, which pumps hot air onto your neck when the roof is down (and it's cold out). You'll also nab heated front seats, power windows front and back and an automatic belt feeder, which saves you reaching over your shoulder to get to your seatbelt. So exhausting.

On the tech front, expect a killer 590W, 13-speaker Burmester stereo, controlled by the seriously impressive widescreen cockpit; two 12.3-inch screens that spill from about the centre of the dash all the way to the driver's binnacle, and control everything from navigation to Apple CarPlay and Android Auto.

There's a whole bunch of safety stuff, including semi-autonomous technology, but we'll drill down on that under the Safety sub-heading.

It’s here where the C-Class is at its most updated, serving up a new turbocharged 1.5-litre hybrid engine in the entry-level C200. Alone, it’s good for 135kW/280Nm, but it’s combined with a clever 48-volt system that adds up to 11kW of bonus power low in the rev range, happily plugging the power void usually left by turbo lag when taking off, or if you plant your foot when overtaking.

The C300 is powered by a more conventional 2.0-litre, four-cylinder good for 190kW/370Nm, while the sole diesel (in the C220d) is a four-cylinder unit that produces 143kW/400Nm. All are paired with a nine-speed automatic transmission.

The C 43 4Matic's engine remains a fabulous thing, only now tweaked for a little bit more power. It's good for 287kW/520Nm, and is paired with a nine-speed transmission that sends the power to all four wheels, albeit with a bias toward the rear tyres.

It's a fabulous engine, this twin-turbocharged V6 - even if it doesn't feel quite so lively in Cabriolet form as it does in the hardtop equivalents.

The 3.0-litre unit produces 245kW/480Nm, sending it to all four wheels via a nine-speed automatic transmission, linked to the standard 4Matic all-wheel drive system.

Let’s start with the C200, where the addition of the clever hybrid system has helped drop fuel use to a claimed 6.0-6.3 litres per hundred kilometres. The old car delivered 6.5 per hundred, but was slightly quicker from 0-100km/h (7.2sec- 7.7sec). 

The C300 will sip a claimed 6.5-6.9L/100km on the same cycle, while the diesel requires a miserly 4.7 litres. The C 43 is the thirstiest, of course, needing 9.1-9.3L/100km on the same cycle. 

The C200 makes do with a 41-litre tank (as does the diesel) while the C300 steps that up to a 66-litre tank. And all those numbers related to the sedan body shape, so expect some slight variations if you’re shopping for a coupe cabriolet or estate.

Mercedes claims 7.4L/100km on the combined cycle (but you can expect to be pushing nine litres in real-world conditions), with emissions pegged at 170g per kilometre of CO2.

The 66-litre tank will only accepts 95RON fuel.

Keen to sample the new hybrid tech in the C200, we made a beeline for the cheapest C-Class. And if you’d told me, even a handful of years ago, that a piddly 1.5-litre engine would be enough to drag the 1555kg Benz around, I’d have labelled you crazier than Donald Trump's Twitter account. 

The C200’s system is a unique hybrid set-up, in the sense that it only delivers extra power in the tiniest of circumstances, but they’re the areas that it really needs it. From a standstill, the electric motor delivers its extra 11kW of oomph at just the right moment need to help get you moving (the same when overtaking) and it does genuinely make a difference. 

It can’t completely overrule the concrete laws of physics, though. Plant your foot on anything that even looks like a hill and you can definitely hear that 1.5-litre engine working hard - interrupting the ambience of the cabin - but keep it in the sweet-spot of the rev range and it’s a quiet, capable-feeling engine that delivers more punch than its size might suggest.

On Germany’s epic autobahns, the needle even sailed past 215km/h without too much encouragement (even if I could have knitted a sweater in time it took to to close the last 10-or-so-kilometres). Is that relevant for Australia? Sadly not, but it does suggest the engine is more capable than we will ever need it to be.

Elsewhere, the not-too-different C-Class rides an absolute dream, smooth-sailing over bumps and road imperfections, and the cabin is serene and comfortable - though there was more wind noise at times than I was expecting.

Downsides? Well, the cheapest C-Class doesn’t feel the most dynamic offering, with the light steering serving up a slight disconnect between the steering wheel and the road below in its most comfortable settings. Switching to Sport improves matters, but if you’re life is mostly city and suburbs, it will matter little.

The nine-speed transmission can behave oddly at times, too; smooth and lightning fast as it climbs the gears, and mostly perfect on the way back down. But I noticed a definite thump occasionally as it shifted down from second to first gear, which stripped a little refinement from the drive experience.

It's more noticeable in the C 43 4Matic AMG, but it's vastly overshadowed by the thick and meaty power delivery from that stonking turbocharged engine. It's a rocket, and while it's not as fast or as loud as its C 63 big brother, I honestly think the tweaked C 43 is all the AMG I'd ever need.

Sure, the E400 Cabriolet can drive itself, but we’re equally pleased to note that it’s still a lot more fun handling the steering duties yourself.

And that is mostly due to that fabulous engine; quiet and effortless at city speeds, rorty and enthusiastic at pace, and genuinely angry with the drive setting switched to their most hardcore Sport+ mode.

We’ve already spent time in the sedan version, and while this Cabriolet is heavier (1935kg vs 1820kg) and slightly slower to 100km/h (5.5sec vs 5.2sec) it doesn’t immediately feel it behind the wheel, with a similar and satisfying lurch into the future when you plant your foot.

But hard charging is not what this car is about, and the E 400 is at its peachy best when rolling about the city or the ‘burbs with the top down, and the warm summer air washing through the cabin.

In its normal drive settings, the steering is light but engaged, and the ride on offer from the standard air suspension is outstanding, cosseting the cabin from all but the very worst road imperfections, while the torque from the V6 serves up effortless, unobtrusive acceleration.

With the roof up, Merc’s designers have done a stellar job of hiding the fact this thing is a convertible at all. It’s a solid-feeling cabin with the fabric roof fastened, and the cabin is quiet and free from wind noise.

There are few cars on the road as overloaded with safety technology as the E400 Cabriolet.

The standard stuff is all there, of course. There's a 360-degree parking camera, as well as nine airbags (dual front, dual pelvic/thorax for front-seat passengers, dual sidebags for rear passengers, dual head bags in the doors and a knee airbag for the driver), rollover protection and tyre-pressure monitoring, as well as braking and traction aids.

But the E400 adds some really clever technology, including Merc's Driving Assistance Package Plus, which adds active lane keeping, blind-spot assist, cross-traffic alert and evasive steering assist.

It's this suite of systems that allows the E400 to navigate freeways autonomously, including changing lanes on demand. At the moment, the system will warn you to keep your hands on the wheel every so often, but you can sense a time when that will no longer be required. And that time is soon.

The E-Class range scored the maximum five-star ANCAP safety rating when crash tested in 2016.

While specific maintenance pricing is yet to be confirmed, each of these models is covered by three-year warranty, with service intervals pegged at 25,000km or 12 months.

Expect the usual three-year, unlimited-kilometre warranty, with service intervals pegged at 12 months or 25,000km. Mercedes' capped-price servicing scheme limits maintenance costs to $2280 for the first three years of ownership.