Mercedes-Benz E400 vs Mercedes-Benz GLA45

What's the difference?

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.

A performance SUV should be an oxymoron and is no doubt a niche product. Is it a high-riding hot hatch? Or a mega-potent small SUV?

Turns out the Mercedes-AMG GLA 45 S is a bit of both and delivers the thrills of a performance car without any of the packaging or comfort-related issues.

While it is getting a little expensive at over $100,000, its blend of space and pace is hard to beat.

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.

The most obvious tell that the GLA 45 S is something a little special is the Panamericana front grille, an ode to the 1952 Mercedes 300 SL, which is found on all of the German brand's hot models.

But if that wasn’t enough to give it away, the reworked bumper with larger intakes, red-painted brake calipers, lower ride height, black exterior trim and 20-inch wheels should help.

Coming round to the rear, if the AMG and GLA 45 S badges aren’t enough to give away this car’s sporting intent, the quad-exhaust tips and diffuser are sure to give any tailgaters pause.

Our car also came with the optional 'Aerodynamics Package', which adds front fender flicks and a massive roof-mounted rear wing for an even racier look.

If you think the GLA 45 S looks a bit like a jacked up hot hatch, you aren’t far off. Overall, we reckon Mercedes has done a great job at translating the aggressiveness of its A 45 hatch to the larger, higher-riding GLA.

Without the aero package optioned, you might even call it a bit of a sleeper, and it’s certainly more subdued in styling compared to its Audi RS Q3 rival.

In fact, the GLA 45 S might be too subtle for such a hot SUV, at least for our tastes.

Whereas the A 45 S and CLA 45 S get bulky fenders and a hunkered-down, aggressive stance, the GLA 45 S could just blend into the sea of SUVs seen out on the streets, especially without the aerodynamics package added.

Your mileage will vary though, and for some, the subtler looks will be a positive.

Anyone who has sat in a recent small Mercedes should feel right at home in the GLA 45 S, and that’s because it shares much of its interior design with the A-Class, CLA and GLB.

As mentioned before, the 10.25-inch centre screen takes care of multimedia duties, but there are also clicky and tactile buttons underneath for climate controls.

Key to the interior design though is an all-digital instrument display, which is laid out on the high-definition 10.25-inch screen.

With two screens facing you, you might think it’s a bit of information overload, but you can tweak each display to show the information you want.

The digital instrumentation might not be as intuitive as Audi’s 'Virtual Cockpit', but the layout and design of the interior is easy to use and offers owners plenty of customisation to get it right.

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.

The new-generation GLA 45 S has grown in all dimensions compared with its predecessor, making it much roomier and more practical than before.

For reference, it measures 4438mm long, 1849mm wide, 1581mm tall and features a 2729mm wheelbase, but still sports a roomy cabin for four adults, especially in the front seats.

Storage options include decent door pockets that will accommodate large bottles, a deep centre storage bin, smartphone cradle that doubles as a wireless charger, and two cupholders.

Being a small SUV, the rear seats also afford plenty of room for occupants, with more than enough space for head, shoulders and legs – even with the front seat adjusted to my 183 cm (6'0") frame.

There are decent door pockets, air vents, and USB-C ports that should keep passengers happy on long trips, but the GLA 45 S doesn’t have a fold-down armrest or cupholders for the rear seats.

The boot, however, is where the GLA 45 S really starts to make a case for itself compared to the A 45 S.

The boot boasts 435 litres of volume, and can expand to a massive 1430L with the rear seats folded – making it about 15 per cent bigger than the A 45 S – while the higher load height should make loading and unloading groceries a bit easier. 

A downside of the GLA’s tech-focused interior, though, is that all the USB ports are now USB Type-C, meaning you’ll likely have to carry around an adapter to use your old cables.

Mercedes is generous enough to include one with the car, but given most device chargers are still USB Type-A, it is something to be aware of. 

Priced at $107,035, before on-road costs, the GLA 45 S not only sits atop the Mercedes-Benz GLA range, but is also the priciest small SUV available in Australia.

For context, the second-most expensive GLA – the GLA 35 – costs $82,935, while the previous-generation GLA 45 was priced at $91,735 – meaning a $15,300 leap for the new-gen version.

The Mercedes-AMG GLA 45 S also easily blows away its Audi RS Q3 in the pricing department, but also for performance (more on that below).

For the price you are paying, you’d expect a long equipment list, and Mercedes doesn’t disappoint in this regard.

Highlights include an automatic tailgate, keyless entry, push-button start, wireless smartphone charger, illuminated door sills, electronically adjustable front seats with heating, LED headlights, and a panoramic glass sunroof. But at this price you are also paying for a kickass engine and prodigious performance.

As with many of Mercedes’ new models, the GLA 45 S makes use of the 'Mercedes-Benz User Experience' multimedia system, which is outputted across a 10.25-inch touchscreen.

Functions on this system include satellite navigation, digital radio, as well as Apple CarPlay and Android Auto support.

Users have many input options, too, from a central touchpad with haptic feedback, the touchscreen, capacitive touch buttons on the steering wheel, or with voice commands.

Being an AMG, the GLA 45 S also picks up a unique steering wheel with yellow contrast stitching, leather interior, snazzy sports seats, as well as unique instrumentation readouts such as engine oil temperature.

Our test car also came fitted with the optional 'Innovation Package', bundling a head-up display and an excellent augmented reality overlay that shows streets in real time on the multimedia screen.

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.

Powering the Mercedes-AMG GLA 45 S is a 2.0-litre turbocharged petrol engine, outputting a staggering 310kW/500Nm.

This means the new car jumps up 30kW/25Nm compared to its predecessor, explaining (at least in part) the price jump.

The GLA 45 S is also the top-spec version globally. The 285kW/480Nm GLA 45 which is available overseas would be more directly comparable to the old car.

The engine is also the most potent production 2.0-litre on earth, and is shared with the A 45 S and CLA 45 S.

Paired to the engine is an eight-speed automatic transmission, which sends drive to all four wheels via Mercedes’ '4Matic' system.

As a result, the GLA 45 S will accelerate from 0-100km/h in a frighteningly quick 4.3 seconds, and carry on to an electronically limited top speed of 265km/h.

This is 0.4s slower than its A 45 S sibling, in part due to its heftier 1807kg weight.

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.

Official fuel consumption figures for the GLA 45 S are pegged at 9.6 litres per 100km thanks in part to an engine start/stop system.

We managed 11.2L/100km after a few days of testing around Melbourne’s inner city and winding country back roads, but those with lighter feet will no doubt come closer to the official figures.

A performance SUV that can ferry kids and groceries, out accelerate  nearly everything else on the road, and sip around 10L/100km? That’s a win in our book.

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.

If the bespoke styling wasn’t enough of a giveaway, all it takes to realise you are behind the wheel of something special is to turn on the GLA 45 S.

The prodigious engine is fantastic in the A 45 S and CLA 45 S and is no different here.

With peak power coming in at a heady 6750rpm and maximum torque available from 5000-5250rpm, the GLA 45 S likes to rev and makes it feel a little like a naturally aspirated engine in character.

Don’t get us wrong, once the boost becomes available, you will feel that shove into the back, but it’s great that Mercedes has made the engine perform a little more predictably.

Paired to the engine is a smooth shifting eight-speed dual-clutch automatic transmission, which is one of the better versions I've experienced.

Many DCT bugbears, such as jerkiness at low speeds and clunkiness when putting into reverse, aren’t apparent here, and the transmission is up to the task when puttering around town or when driving spiritedly.

Speaking of which, the GLA 45 S’ different drive modes will easily change its character from tame to wild, with available options including ‘Comfort’, ‘Sport’, ‘Sport+’, ‘Individual’ and ‘Slippery.’

Each mode will tweak the engine response, transmission speed, suspension setting, traction control and exhaust, while each can also be mixed and matched in the ‘Individual’ drive mode.

However, a missing feature for the GLA 45 S that is found in its A 45 S and CLA 45 S siblings is a drift mode.

Sure, how many small SUV owners are going to take their car to a track to make use of it, but it still would have been nice to have the option.

With three levels of suspension setting, though, the GLA 45 S offers enough variability to be comfortable around town and soak up the bumps thanks to its long suspension travel, while also switchable for a more involved, driver-focused feel.

The GLA 45 S might never corner as hard or fast as its A45 S sibling, but being an SUV brings its own unique set of plus points.

At the time of writing, the new-generation GLA – including this GLA 45 S – has yet to be crash tested by ANCAP or Euro NCAP.

However, standard safety equipment extends to autonomous emergency braking (AEB), lane-keep assist, blind-spot monitoring, traffic sign recognition, adaptive cruise control and a surround-view monitor.

The GLA also has nine airbags spread throughout the cabin, as well as an active bonnet and driver attention alert.

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.

Like all new Mercedes-Benz models, the GLA 45 S comes with a five-year/unlimited kilometre warranty with five years of roadside assist – the benchmark in the premium car space.

Service intervals are every 12 months or 20,000km, whichever occurs first, and the first five services are available to purchase for $4300.

This actually makes the new GLA 45 S cheaper to maintain over its first five years than the outgoing car, which costs $4950 over the same time period.