Mercedes-Benz GLE400 vs Lexus RX450H

What's the difference?

All told, the Mercedes-Benz GLE 2020 model is an improvement in many ways over its predecessor. It's safer, more high-tech, considerably more luxurious and practical inside, and offers better value, too.

But, in 300d guise at least, it's let down by a slightly underdone engine, and suspension that just doesn't do a good enough job on rougher roads. It's close, but not close enough to be best in class.

Maybe that'll be a different case for the higher-grade versions with the most high-tech engines and the tricky optional suspension... we'll have to wait and see.

The RX is a little frustrating - it's going after Mercedes and BMW and Audi in a hotly-contested space and falls over in a couple of key areas. The media/sat nav system is hopelessly outdated and the drivetrain fails to deliver a significant performance or fuel benefit (although, given its 2.2 tonnes, perhaps it delivers a miracle).

It does come with a rock-solid, scandal-free reputation, a reputation for spectacular customer service, it has a lovely cabin and it's certainly an individual looker. For plenty of people, that's quite enough.

You can make your own mind up about the styling of the new GLE. It's certainly more aggressive than the model that came before it, and Benz claims that it's the most aerodynamic SUV in its class.

The models on test were all fitted with the AMG styling pack and the bigger 21-inch multi-spoke wheels, and from some angles it's a striking car. I particularly like the way the rear-end treatment has worked for the GLE: the triangulated tail-lights, the lower bumper and the rear glass all work together well.

In profile, the GLE is quite challenging to look at. The rounded window-line is a bit awkward, and somehow the wheels just don't fit with the bulky guards (though I do like the way the AMG 21s poke out a bit at the back).

The front sees the diamond-style treatment to the grille for the AMG Line versions, but there's a lot of black plastic on the bumper, and the headlight shape gives it a bit of a droopy-eyed look. Is it just me, or is it a bit of a Bassett Hound? 

It is a bigger car than before - 111mm longer (now 4930mm - and on an 80mm longer wheelbase, now 2995mm), and it's 15mm wider but 31mm lower - and it looks more substantial as a result. I'm just not sure it's pulling off its bulk as well as it could.

So the outside is pretty, er, interesting. We had comments from passersby to that effect, too, and in our comparison test it was the consensus of our team of experienced testers that the GLE had some challenging exterior design elements.

But inside is where the best bits hide, with a lot of luxury finishes, materials and technology giving the GLE some wow factor that its exterior design arguably misses out on.

There's a lot of RX and there's a lot going on in that creased, folded and teased sheetmetal. It's a unique design, with a huge 'spindle grille', big lights and the fast glass both front and rear.

It positively screeches Lexus DNA and was a polarising force on our driveway for the week. Most weren't sure, but knew for certain it was a Lexus.

Aggressively flared wheelarches like this aren't common on SUVs (although the squared-off ones are). It's right up on stilts, but the 20s you find it rolling on help to reduce its visual bulk.

That wacky rear quarter glass reminds me of the BMW i3's but it's a Lexus SUV signature. It's quite striking. Do I like it? Not really, but that's completely subjective. You can tell, though, it's built tight as a drum.

Inside is a bit calmer, beautifully laid-out and built to last. The materials are almost all top notch, with lovely switchgear and the real leather is really nice.

There is absolutely nothing avant-garde in there (apart from maybe the pinstripe effect on the centre console), it's all terribly comfortable and easy on the eye. But not exciting, though not all Lexuses are.

This particular car is very US-centric and, if I may, a particularly sunny and humid part, so it can't be too wacky.

The cabin presentation and pragmatism is excellent in the new-generation GLE. There was an existing version on site for us to compare, and to say it's like night-and-day would be generous to the old model.

A lot of that comes down to the MBUX twin 12.3-inch screens on top of the dash - one for all the driver instrumentation and controls, and the other for sat nav, media, car controls and other settings. They look great, and there are multiple ways to control them: the steering wheel controls, the touch pad between the front seats, the screen in the middle is touch-capacitive, and there's the much-bragged-about “Hey Mercedes” voice control system.

But it's more than just the screens: the finishes and materials used in the GLE are exceptional. The plastics are excellent, the brushed aluminium treatment that runs the width of the dash with ambient lighting, the surrounds on the vents (oh, so many vents!) - it all works so well together. But the open-pore wood finish is my favourite element, adding a touch of ruggedness that's also plush and luxurious.

The test cars all had the high-end leather treatment and optional bolster-heavy seats, and they're okay, but a little fiddly to adjust. I guess that's the beauty of driver profiles - the car will remember your favourite settings and make the adjustments as you get in or out by detecting the key.

There's also excellent storage throughout - the door pockets in all four doors are huge, there are cupholders front and rear, and loose item storage is decent, too. Plus there are heaps of USB-C (fast charging) ports up front and in the back.

Speaking of the back, the cars at launch all had the seven-seat package, which might appeal to you, or not. It's more than just a couple of seats in the back row, because it includes electric seat adjustment for the second row, with slide and recline functions allowing you to prioritise second- or third-row space.

The space in the second-row with the seats set as far back as they can go is excellent. There's heaps of room for someone my height (182cm) to sit behind a similar sized driver with ample knee room, headroom and shoulder room. You'll be able to fit three adults across the back, or if you have kids, there are three top-tether points and outboard ISOFIX child-seat anchors, too. No child seat restraints in the third row, though.

Whether you choose the five-seat or seven-seat option, the boot space remains the same at 825 litres with five seats in play. All models have an electric tailgate, too.

And if you're curious about the third row, it should be fine for anyone shorter than 175cm for shorter drives. It's not super spacious back there, and should be considered a 5+2 option. Really need a seven-seat Merc? You could get a GLS if you can afford it, or go for a V-Class luxury van. Go on. Do it!

There is plenty of room inside this big unit, which is very welcome. Front seat passengers have lots of storage, such as a deep central bin under the armrest, dual cupholders and big door pockets with bottle holders.

Step into the rear and there is a ton of leg and headroom although the transmission tunnel intrudes slightly for the middle passenger. Chuck them out, drop the armrest and you have two more cupholders and each door has pockets and bottle holders.

The boot is pretty big considering the angle of the rear glass. You start with 453 litres (but an expanse of flat floor), which rises to 924 litres with the split-fold seats down. That seems conservative given just how much space you appear to have.

The RX450h F Sport lightens your bank account of $102,460 before on-road costs, the only hybrid SUV within cooee of this price.

That nets you 20-inch alloys, a 15-speaker stereo, dual-zone climate control, heated and cooled electric front seats, reversing camera, that ever rare CD player, keyless entry and start, a solid safety package, reversing sensors, active cruise control, sat nav, a massive sunroof, auto LED headlights, head-up display, partial leather interior, power tailgate, auto wipers and a space-saver spare.

The Lexus media system is run from the gigantic dash-mounted screen that is shamed only by those massive Tesla units.

Sadly, the joystick-style control remains as does the very confusing software system that is less than delightful to use. It's such a shame that a tech-laden machine is let down by the world's most baffling entertainment system.

Once you get it working and understand it, it's okay, I guess, but several years into this job I still can't easily fathom how it works. And that naff analogue clock...

F Sport cars also pick up adaptive suspension and a several driving modes to liven things up.

Powering the Mercedes-Benz GLE is a selection of engines, with petrol and diesel offered.

The entry-level power plant is the 300d, which uses a 2.0-litre four-cylinder turbo-diesel engine with 180kW of power (at 4200rpm) and 500Nm of torque (from 1600-2400rpm). It has a nine-speed automatic transmission and all-wheel drive as standard.

The range-topping diesel is a thumper. It's the 400d, which runs a 2.9-litre turbo-diesel six-cylinder with 243kW of power (at 4000rpm) and 700Nm of torque (from 1200-3000rpm). It also has a nine-speed auto and AWD standard.

The sole petrol model at launch is the 450, which employs a twin-turbocharged 3.0-litre in-line six-cylinder engine with 270kW of power (at 5500rpm) and 500Nm (at 1600-4500rpm). It uses a nine-speed automatic transmission with AWD, but this version is the only one with mild-hybrid tech, using 48-volt EQ Boost tech to help add 16kW and 250Nm for short stints of added performance (0-100km/h in just 5.7 seconds, apparently), and allowing the engine to shut off under light throttle or lift-off situations.

If you plan to tow, there's a factory-fit tow pack available that allows 750kg unbraked and 3500kg braked towing across all grades. This pack is the one from the factory - remember that - and it costs $1900. If you instead fit one as an aftermarket fit, the figures are 750kg/2700kg respectively.

You can choose three different powertrains in the RX - a 3.5-litre V6, a 2.0-litre turbo four-cylinder, or this one, the 3.5-litre V6 with hybrid.

As a series hybrid it can run for short distances on electric only before firing up the V6 to supply charging and motivation.

The 3.5 produces 193kW/335Nm along with the electric motor. That torque figure seems low and it probably is, but that's a function of the weird way of measuring torque from a hybrid unit. The combined power figure, however, is 230kW.

The hybrid system is hooked up to Lexus' CVT auto and sends power to all four wheels. Lexus says the 450h will complete the sprint from 0-100km/h in 7.7 seconds, which isn't bad for a 2210kg SUV.

Fuel consumption varies between the models, as you'd expect.

The 300d is the most frugal of the mix, with an official combined cycle fuel use claim of 6.9 litres per 100 kilometres. The 400d, with its bigger six-cylinder diesel, is said to use 7.7L/100km. The 450 petrol model has the highest claimed fuel use, at 9.1L/100km, and that's despite the fact it's the only version of this trio to bring electrification into the mix with the EQ Boost 48-volt mild hybrid system.

On test at the launch of the GLE we saw a displayed return of 9.4L/100km for the 300d model, but there was a fair bit of country road and highway driving in the mix.

All versions of the GLE are fitted with an 85-litre fuel tank.

The official combined cycle figure is listed as 5.7L/100km. And, uh, yeah, we didn't get that. I did manage 8.9L/100km over the week, which included a long motorway run from Sydney up to the Blue Mountains (a roughly 160km round trip).

The launch drive was limited to the 300d variant, though I did get a chance to sample the version with air suspension, as well as the model with the standard steel suspension.

Now, before we get too nerdy, this is an important element for a luxury SUV. Ride comfort is arguably as vital as effortless power. And, sadly for the GLE, neither model sets any benchmarks for suspension control and comfort.

The steel-sprung model doesn't have adaptive suspension at all, meaning that it can be bouncy, wobbly, unsettled and stiff all at the same time. The country road I sampled it on showed that the standard suspension offered up a quite nervous experience, never feeling as settled as a luxury SUV really ought to.

The air suspension version is definitely better, but still not as good as a BMW X5, Audi Q7 or VW Touareg. It lacks the body control and comfort that a true luxury SUV ought to offer.

Now, that might matter to you, or it might not. You might think the look of the car - with 20s, 21s or 22s filling the guards - is more important than how it deals with lumps and bumps. But it's our job to tell you how the land lies, and the GLE simply can't match the better SUVs in this segment as a driver's tool.

There is another level of suspension which the CarsGuide team (myself included) hasn't yet had the chance to sample - the E-Active Body Control system, which includes curve-tilting so it can make the car feel level through corners, and a system that'll scan the road ahead to predict bumps and lumps and prime the suspension to deal with it. That system is $13,000... and, while I haven't sampled it yet, it's my hope that it makes all the difference to the GLE.

So, what about the other driving elements? Well the steering is light and accurate, and decently responsive at low speeds or highway pace, and you're never left guessing as to what'll happen.

The engine, too, is decent - a 2.0-litre with 180kW and 500Nm is nothing to be sneezed at - but in a vehicle this large, with a kerb weight of 2165kg, and with a nine-speed automatic taking care of forward progress, it can be a busy engine.

That's because the transmission will shuffle between ratios when you encounter a hill as it doesn't quite have the grunt to simply stick in a gear and tug you along. It's not that big of a deal, and the transmission is smooth enough and pretty hard to catch out, but it is a little less effortless than a six-cylinder would no doubt be.

All in all, I was left wanting more from the drive experience. Maybe the higher-grade models with the highest-grade suspension will prove a better flag waver for the new-generation GLE.

Right. So this is a salutary lesson about tyre pressures. The first few days the tyres were only pumped up to 200kpa (29psi). That's an easy 100kpa (14psi) short of the required 300 (43psi).

Every time I, or my wife, went around a corner, the big Dunlop Sport Maxx SPs would squeal and squirm and it was most unsatisfactory.

So check your tyres, because the extra 100kpa makes all the difference. Also, the number of service stations it took to find a working pump was unacceptable. Pull your socks up, Sydney.

Anyway.

Correct tyre pressures enacted, the big Lexus turned into a comfortable, competent cruiser. Its motorway performance is super-impressive, purring along the M4 and it's ridiculously poor surface like it was born to it. Which it sort of was.

The hybrid drivetrain allied to the CVT is mostly whisper quiet. It's not the most responsive combination, the initial step-off of the electric motor's torque soon giving way to the rubber band effect of the transmission.

It doesn't feel as swift as the claimed 7.7 seconds and it would be nice if the drive select dial made a genuine difference to the throttle and transmission's response.

In the city, it's a proper wafter, moving about the broken down city streets of Sydney without fuss and a plush ride that's a bit of a surprise given the huge wheels and substantial weight of RX.

It's all very easy and pleasant but the wild looks do not match the experience. Which is not a criticism, just an observation.

The RX ships with eight airbags (including knee airbags for both front seats), ABS, stability and traction controls, blind spot sensor, reversing camera, forward collision warning, forward AEB and reverse cross traffic alert.

There are three top tether restraints and two ISOFIX points. 

The RX scored a maximum five ANCAP stars in January 2016.

Mercedes-Benz stands by its three-year/unlimited kilometre warranty plan, stating at the launch it has no plans to extend it to match what most of the mainstream brands now offer (five years). But it's not alone in the luxury segment in that regard.

The big point the company's local reps made was that they're trying to lower the cost of ownership for customers through servicing packages. You can pre-pay them, or you can pay as you go (PAYG).

The GLE requires maintenance every 12 months or 25,000km. The pre-pay option is $2700 for the first three years/75,000km of maintenance or, if you decide to PAYG, the costs are $850, $1200 and $1250 (totalling $3300 over the same period). It makes sense to pre-pay then, and you can bundle the cost into your finance, too, so you'll notice it less.

There is three years roadside assist included at no cost if you buy the car brand new, as it coincides with the warranty period.

Lexus offers a fence-sitting four year/100,000km warranty with roadside assist thrown into the bargain for the same period. 

Service intervals arrive at 12 month/15,000km and there is, sadly, no capped-price servicing.

Lexus will, however, promise you a car for the day or come and get your car from you and drop it back when the service is done. And it will be washed and vacuumed. The website makes a big deal about that.