Mercedes-Benz E-Class vs Lexus RX450H

What's the difference?

The Mercedes-AMG E53 Hybrid 4Matic+ is a superb blend of high-tech hybrid muscle and cossetting top-end luxury. Value is competitive, it looks (and feels) the business, despite the conventional sedan configuration it’s surprisingly practical (except for the modest boot), fuel-efficiency is a key benefit and safety is stellar. The ownership proposition is okay for the category but that’s not top of mind when an enticing series of corners ranges into view. It’s an impressive package.

Note: CarsGuide attended this event as a guest of the manufacturer, with travel, accommodation and meals provided.

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 The media/sat nav system is hopelessly outdated and the drivetrain fails to deliver a significant performance or fuel benefit (although, given its 2.2 tonnes, perhaps it delivers a miracle).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.

At first glance the E53 passes as a flash-looking Mercedes-Benz E-Class running 20-inch rims, especially in the launch car’s rich ‘Patagonia Red’ finish.

But then, there’s something about the AMG sedan’s stance that sets it apart. Which makes sense because the front fenders are wider by 11mm on both sides (compared to the E-Class) to make room for a wider front track (increased by just over 30mm over the previous-generation E53).

Wheelbase has also increased by just over 20mm to almost 3.0m and the car’s more aggressive nose treatment enhances the distinctive look.

There’s the AMG-specific radiator trim with ‘Panamericana’-style vertical slats, the sleek dual-section headlights and a large lower inlet that directs air to an additional front intercooler as well as an external opening for a wheel-arch cooler.

In profile there’s barely a hard edge to be seen, although character lines in the bonnet and along the car’s flanks contribute to a taut surface treatment.

At the rear, horizontally-connected LED tail-lights feature a stylised Mercedes three-pointed star signature, then a rear apron housing a diffuser and twin double tailpipe ‘trims’ and a bootlid spoiler on the left and right round off a beautifully proportioned design.

Climbing inside means a trip to screen city with an upright digital display in front of the driver flanked by a large central screen to the left and an additional panel for the front passenger beyond that. It’s a lot.

But once you’re on top of all the glass surfaces, details like open pore grey ashwood trim on the lower console come into focus, as do the brushed metal accents, beautifully sculpted ‘Performance’ front sports seats (optionally fitted to our launch drive example), racy stainless steel pedal covers and the five spoke AMG performance steering wheel with configurable rotary buttons.

It’s a supremely luxurious and comfortable interior. 

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.

At over 4.9m long, close to 2.1m wide and a little under 1.5m tall, with a 2961mm wheelbase, the new E53 is a substantial car and feels it on the inside.

Plenty of breathing space for the driver and front passenger thanks in part to the away slope of the screen-dominated dash.

Generous storage, too, with large door bins including enough space for big bottles, a deep lidded box between the seats (which doubles as a centre armrest), a generous glove box and two cupholders under a sliding top at the front of the centre console. 

Hit the second row, and sitting behind the driver’s seat, set for my 183cm position, I have plenty of head and legroom, with enough shoulder space for three adults on short journeys. A trio of up to mid-teenage kids will be fine for a road trip.

Storage is pretty handy as well with hefty door bins and two pop-out cupholders in the fold-down centre armrest. No map pockets on the back of the (optional) Performance front seats, though.

Four-zone climate control means there’s individual temperature control for each side of the back seat, with adjustable vents at the back of the front centre console and trailing edge of the B-pillars. Very civilised.

Power and connectivity runs to three USB-C outlets and a wireless device charging pad in the front.

Thanks to the traction battery under its floor, boot volume is restricted to 370 litres (compared to 540L in the conventional E-Class sedan), although there are bag hooks, tie-down anchors and the 60/40 split-folding rear seat is able to liberate more space.

No spare tyre of any description, just a repair/inflator kit, which might make sense for automotive designers and engineers trying to maximise space and reduce weight, but doesn’t make sense for an owner stranded on the side of the road with an unrepairable puncture.

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.

The E53 is powered by a 3.0-litre, turbo-petrol, in-line six-cylinder engine working in concert with an electric motor housed within the car’s nine-speed (torque-converter) automatic transmission. 

Drive goes to all four wheels via an electro-mechanically controlled clutch distributing power between the front and rear axles.

Engine performance is up by around 10kW compared to the previous E53 thanks to software upgrades, a new twin-scroll turbo with higher boost pressure (1.5 bar vs 1.1 bar) as well as additional front and wheel-arch intercoolers. 

The engine alone produces 330kW/560Nm while the permanently excited synchronous motor chips in with a solid 120kW/480Nm for overall outputs of 450kW/750Nm.

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.

The E53’s official combined cycle (urban/extra-urban) fuel figure is 1.7L/100km, a spectacularly frugal number for such a high-performance machine. But it’s worth noting it’s predicated on the drive battery being constantly and completely recharged.

Speaking of which, the 28.6kWh, 400-volt traction battery is housed at the rear of the car under the boot floor. It delivers a claimed EV-only range of up to 100km, although that will diminish dramatically if you decide to push up towards the car’s pure-electric top speed of 140km/h.

Important to note the battery’s 21kWh ‘day-to-day’ capacity, designed to keep charge in reserve for any required ‘high-performance boosts’.

An 11kW AC charger is onboard with regenerative braking also harvesting energy, the car automatically selecting the level of recuperation power in line with traffic conditions.

In pure EV mode you can also manually adjust regen through four levels via the steering wheel-mounted transmission shift paddles. 

Auto stop/start for the engine is standard and 98 RON premium unleaded is recommended, although 95 RON is okay at a pinch.

The E53’s official fuel consumption figure and 50-litre tank capacity translate to a range approaching 3000km! But to bring that down to earth somewhat, on the launch drive program, covering urban and mostly highway running, we saw a (dash indicated) average of 6.4L/100km, which equates to a more realistic, but still lengthy, 780km between fills.

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).

If you’re lining up for a Mercedes-AMG you want an optimal blend of luxury and performance and the E53 Hybrid 4Matic+ nails that delicate balance.

With 450kW (that’s 612hp!) and 750Nm under your right foot, engaging ‘Race Start’, pushing the accelerator to the floor and letting the car do its thing will result in 0-100km/h acceleration in 3.8 seconds. The fat band of mid-range torque is so satisfying to lean into.

Induction, engine and exhaust sounds combine to produce a suitably gruff soundtrack with the hybrid powertrain operating seamlessly. Hit your preferred track day or tempt legal fate and you can explore the car’s claimed (governed) maximum velocity of 280km/h. 

The nine-speed auto is slick and manual changes using the wheel mounted paddles are rapid.  In normal conditions the AWD system is biased to the rear and an electric rear locking diff helps keep things under control if you decide to get the bit between your teeth on a twisting drive.

A chunky brace links the front suspension strut mounts and the car feels predictable and stable in enthusiastic cornering. Rubber is Michelin Pilot Sport 4S (245/35 fr / 275/30 rr) which grips with satisfying determination but does make its rumbling presence felt on anything approaching a coarse chip surface (despite the car’s standard acoustic glass).

Speed-sensitive power-steering delivers accuracy and good road feel without any jitters, the standard active rear-axle steering playing its part. The ‘turning point’ is 100km/h with the rear wheels subtly turning in the opposite direction to the fronts up to that speed and in the same direction beyond it.

‘AMG Ride Control’ combines steel spring suspension (strut front, multi-link rear) with adaptive adjustable damping for the choice of ‘Comfort’, ‘Sport’ and ‘Sport+’ settings. Comfort is the pick for B-road running on typically uneven surfaces. The optional ‘Performance’ sports front seats are comfortable and grippy in equal measure. 

Braking is by ventilated composite rotors all around, with beefy four-piston fixed calipers up front. An electro-mechanical brake booster is designed to combine electrical recuperation with the hydraulic brake for more frequent and efficient energy harvesting over a longer period of time. The pedal feels firm and progressive with smooth initial bite. 

All around vision is good for a conventional sedan with a quality reversing camera, 360-degree overhead view and front and rear parking sensors helping massively with parking duties. That said, a 12.5m turning circle isn’t tiny.

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.

The Mercedes-AMG E53 Hybrid 4Matic+ is covered by a five-year/unlimited km warranty with the high-voltage battery covered for eight years/160,000km. Those terms match the key players in the premium and luxury parts of the market.

Mercedes-Benz ‘Road Care’ assistance is included for the duration of the main vehicle warranty. 

Maintenance is recommended every 12 months/25,000km, with service plans offered across three- ($4110), four- ($5410) and five-year ($7570) periods. That’s an average of around $1350 for the first two and $1500 for the last one. That added powertrain complexity obviously has an impact in the workshop.

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.