Mercedes-Benz S-Class vs Lexus Rx450H+

What's the difference?

Mercedes-Benz set out to restore the S-Class' place amongst the greatest sedans in the world.

In the heavily-optioned, near-$250K-plus S450 as well as the extended S450L at $300K as tested (the sweet spot of the range for now), we reckon the Germans have succeeded, pushing safety, comfort and technology boundaries, in a package that is true to the heritage of the series.

Tax-fuelled sky-high prices will certainly keep the S-Class niche in Australia, but the car is more than good enough to dominate its tiny corner of the upper-large luxury car sphere.

The best new car in the world? We reckon it's highly likely. Mission accomplished, Mercedes.

The new Lexus RX450h+ Sports Luxury is packed with a wealth of premium features and strikes a solid balance between refinement and practicality. There are enough thoughtful touches that make everyday driving a little easier.

You’ll get the most out of the plug-in hybrid powertrain if you’re able to charge it regularly; ideally every day. That might not always be practical for busy people on the go, but overall, the RX450h+ manages to blend efficiency with Lexus’ signature comfort and quality.

Most Mercedes models have followed the Russian Doll-style cookie-cutter styling theme, and the heavy family look continues with the W223.

Still, the flush door handles do add a touch of Tesla-esque modernity, while the elegant silhouette and clean lines are in keeping with the luxury aspirations. Larger in every dimension compared to the old W222, the S450 is some 71mm-longer in wheelbase (3106mm) than before while the LWB's has stretched out by 51mm (3216mm), benefiting proportions as well as interior packaging.

AMG-branded wheels look sporty but – in the S450 at least – they're perhaps a tad too gangster. A set of flush alloys would give it a more-modern and techier appearance, in our opinion.

Overall, however, the S-Class ‘7' possesses the prerequisite richness of design. It isn't as bold and mould-breaking as models like the W116 were back in their day, but the styling is still a success.

By the way, the latest S-Class is the first Mercedes to employ the MRA2 longitudinal platform, which is rich in lightweight steels (50 per cent aluminium), is correspondingly stronger than before but also 60kg lighter.

With a drag co-efficiency rating as low as 0.22Cd on some overseas grades, the W223 is one of the most aerodynamic production vehicles in history.

The RX isn’t breaking new ground with its plug-in hybrid design, but it still delivers that signature Lexus understated refinement.

The strong, flowing body lines, 21-inch alloy wheels and updated 'spindle grille' all give it presence without screaming for attention.

And in a segment where boxy and bulky designs tend to dominate, the RX’s swoopy silhouette helps it stand apart in all the right ways.

Inside, the cabin feels considered and luxurious. There's a heavy use of premium materials, including the leather and suede upholstery, plush soft-touch surfaces and the big, crisp displays that make the space feel modern and high-end.

The panoramic sunroof brings in loads of natural light, too, which is especially welcome given the dark headliner that might otherwise feel a little heavy.

If I have one gripe, it’s the thin steering wheel, which doesn’t quite match the otherwise solid, tactile feel of the rest of the interior. But overall, the cabin is a space that feels luxurious and well-executed. It's quietly confident, just like the RX.

For the beginning of our day with the S-Class, we were chauffeured from home to a mansion in Kew, a blue-chip Melbourne suburb. Our heavily-optioned S450L featured most of the aforementioned extras – including the Business Class Package and Rear Entertainment Package – and the experience was predictably, sumptuously memorable.

Reclining individual rear seats with easy-reach tablets, armrests offering access to all multimedia and available climatised and massaging cushions and backrests... we're no longer in our normal ride, Toto.

Yet, all these trinkets and gizmos are mere add-ons, that can turn a stretched Caprice into a flash hen's night carriage if enough money and glitz is thrown at it.

No, the new S-Class must impress in an altogether less tangible and more philosophical manner, involving all the senses, and not just what we see, hear and touch. It must appeal beyond the superficial. Otherwise, it is not a large Mercedes-Benz luxury sedan in the classic manner.

This is a Herculean task for the Stuttgart designers and engineers. By and large, though, the Three-Pointed Star has succeeded in achieving something special.

In its perception of peerless quality and engineering, the W223 is striving to move forward and look back simultaneously to the glory days of the seminal W126 (1980-1991). This is through meshing traditional virtues like solidity and quality materials while dazzling its passengers with technology that is still friendly enough to want to enhance your experience.

You can sink into the soft lounge seats, watch the world pass by silently outside and never be aware of the road underneath or the engine ahead. Double glazing, exquisite and aromatic fabrics and materials and lush tactile surfaces work their magic inside the car, while an airtight and aero body, solid platform, air suspension and a muted yet muscular powertrain all do their thing underneath. The atmosphere is special and rarefied. That's what an S-Class needs to be and that's what is happening in our $299,000 (as tested) S450L.

The same more-or-less applies up front, as the same trim, leather, wood and technology surrounds the driver and passenger. The spectre of the car that is surely The Car of the Last Decade – Tesla's Model S – is evident in the portrait touchscreen and sparse, almost wallflower dashboard design and layout. No big imposing architectures here.

Yet, while the American upstart actually takes stuff away, the S-Class packs the cabin with subtle features that – like when the planes stopped flying last year and the birdsong subsequently returned – only become obvious once the cabin's design simplicity clears all the white noise for you to be in a better frame of mind to enjoy them.   

Take the haptic interface, for example, as it is perhaps the best we've experienced; the sense of well-being garnered from the cumulative effects of profound seat comfort (the massaging function was never switched off), cocooning micro climate environmental control, orchestral levels of audio entertainment and the theatre of light and vision performed by the two available screens; it is an automotive experience like no other. And the eye-tracking 3D-effect navigation set within the electronic instrumentation. No need for cinematic glasses to get the effect. The driving position itself, by the way, is also first class.

Room to stretch and grow for sure, and in every direction. But room for improvement? You betcha.

Your tester had a headache after a little while staring at that woozy 3D map. The central vents – four at the front, two in the rear – look and feel cheap, leaving us mentally redesigning them; they are frightfully out of place here; the carryover column-stalk auto lever should have been binned in 2005. And, even though the digital instruments have a number of options, none are elegant enough for the S-Class. That's an especially subjective criticism, clearly, but one that – in the context of classic Mercedes luxury sedan contenders – is justified given how timeless the Bruno Sacco era of Daimler design was. Look him up, kids.

Still, after a couple of hours behind the wheel, with our senses reset to calm, it is obvious that the S-Class cabin is a unique and wonderful place – as it should be at a cool quarter-of-a-million dollars.

Job done.

PS At 550 litres (20L more than before), the boot is massive and luxurious enough to sleep in.

The RX cabin is thoughtfully laid out and impressively practical, with a premium feel that doesn’t come at the cost of everyday usability.

Up front, there’s plenty of space for driver and passenger, yet the stepped dash design brings a sense of intimacy. The electric front seats are seriously comfortable, with four-way lumbar support and extra adjustment functions that make this an easy choice for long drives.

Storage options are generous, too. There’s a clever dual-opening centre console, large glove box, multiple phone-sized shelves, map pockets and a couple of cup- and drink holders in each row.

Charging is taken care of by four USB-C ports, one USB-A port and a wireless charging pad.

Tech is up-to-date and well-integrated. The upgraded 14-inch media display looks crisp, supports wireless Apple CarPlay and Android Auto, and is paired with a revamped 12.3-inch digital instrument cluster and a colour head-up display.

The cluster’s new layout is modern and much easier to read than the previous offering. The digital rear view mirror also earns its keep when the cabin’s packed with passengers or gear.

One of my favourite touches? The seat controls on the side of the front passenger seat. It makes quick work of moving the seat forward, especially helpful when you’ve got a kid clambering in with a school bag full of projects.

Access to the rear row is easy, but the stadium-style seating, where you're perched noticeably higher than those in the front, won’t be for everyone.

That said, the rear seats are plush and padded, though they lack side bolsters, which rear passengers might notice during cornering.

Legroom is generous and the hardened kickplates are a dream to clean when your child’s treating the seatbacks like a climbing wall.

My eight-year old gives the back seat a glowing review, thanks to its creature comforts, including rear climate control, directional air vents, seat heating/ventilation on the outboard seats, two USB-C ports and retractable sun-blinds, which are a crowd favourite in our household.

There are three top-tether anchor points, and the bench is wide enough to fit three child seats, though bulky booster seats might be tricky due to the raised seating height.

At the back, the boot is well set up for families, offering electrically folding rear seats, a 12-volt socket, flat loading floor, and a hands-free powered tailgate.

Under the floor, there’s a small compartment for your charging cables (Lexus throws in two!) and a usable 612L of capacity when all seats are in use. One downside, though, is the lack of a spare tyre as you just get a tyre repair/inflation kit.

There are four variants in the RX range, and we’re testing the 450h+ Sports Luxury AWD, which sits just below the flagship and packs in plenty of premium kit for its $123,500, before on-road costs, price tag.

That makes it slightly more affordable than its main PHEV rivals; the BMW X5 xDrive50e (from $125,885 MSRP) and the Volvo XC90 Ultra (from $124,466 MSRP).

The Volvo does offer seven seats to the Lexus’ five, which may matter for larger families, and both rivals also outdo the RX on electric-only driving range - 65km in the RX compared with 77km in the Volvo XC90 and a generous 101km in the BMW X5.

Still, the RX fights back with a seriously stacked features list. Highlights include a panoramic sunroof, 10-way powered front seats with heating and ventilation, electrically folding rear seats (also heated and ventilated in the outboard positions), and a heated, power-adjustable steering wheel. Sound is taken care of by a premium 21-speaker Mark Levinson surround system.

Technology has had a solid upgrade with the 14-inch touchscreen multimedia display, 12.3-inch digital instrument cluster, digital rearview mirror, colour head-up display, live traffic navigation, wireless Apple CarPlay and Android Auto, 4G connectivity, four USB-C ports, one USB-A port and a fast wireless charging pad.

There’s also access to the 'Lexus Connected Services' app, allowing you to remotely lock or unlock the vehicle, pre-set the cabin temperature via three-zone climate control, configure driver profiles and even use your phone as a digital key.

Practical features include keyless entry and start, rain-sensing wipers, dusk-sensing LED headlights, rear sun-blinds, intelligent seatbelt reminders for the first two rows, a child presence alert and a hands-free powered tailgate. However, due to the plug-in hybrid system there’s no spare tyre, just a tyre repair kit.

Where are the V8s?

Right now, the only W223 you can buy is powered by an all-new 2999cc 3.0-litre in-line direct-injection six-cylinder turbo petrol engine dubbed the M256, complete with double overhead cams, an electric compressor intercooler and assistance from a 48-volt mild hybrid system and integrated starter-generator, adding 16kW and 250Nm to the 270kW of power at 6100rpm and 500Nm of torque from 1600-4500rpm.

The 9G-Tronic torque-converter automatic transmission and 4Matic all-wheel drive system combination is a first for the S-Class in Australia.

Top speed is limited to 250km/h, while the 0-100km/h sprint-time takes just 5.1 seconds in both models. Impressive for a two-tonne-plus luxury limo.

Under the bonnet the RX450h+ Sports Luxury runs a plug-in hybrid powertrain that pairs a 2.5-litre four-cylinder petrol engine with a CVT auto and dual electric motors - one on each axle. Together, they produce a total of 227kW of power, though Lexus doesn’t quote a combined torque figure.

Still, it’s quick off the mark for a large SUV, with a 0-100km/h time of 6.5 seconds. There’s more than enough grunt for daily driving and overtaking, even if it doesn’t quite match the outright power of its key PHEV rivals.

With the aid of the mild-hybrid system, the S450 returned a combined average of an impressive 8.2 litres per 100km, which translates to 187 grams of carbon dioxide emissions per kilometre. 95 RON premium unleaded (or higher) is recommended. In the urban run it consumes 11.3L/100km (11.5 for S450L), and just 6.4L/100km (6.5 for S450L) in the extra-urban result.

At 76 litres, the fuel tank will allow a combined average range of about 927km between refills.

The plug-in hybrid system brings solid efficiency, with claimed fuel use of just 1.3L/100km. In real-world conditions (mostly urban driving with regular recharging) I managed a respectable 4.8L/100km, which makes a strong case for the hybrid set-up.

The fuel tank holds 55 litres and it's worth noting Lexus recommends using a minimum of 95 RON unleaded petrol to fill it.

Using our real-world economy figure you can expect a range in excess of 1100km between fills.

The RX450h+ is fitted with a relatively small 18.1kWh lithium-ion battery, supporting an NEDC electric-only range of up to 65km.

While that’s fine for short daily trips, it’s shorter than you'd ideally want in a family SUV of this size and it lags behind rivals like the BMW X5 and Volvo XC90 in this department.

Charging is simple enough. The RX uses a Type 2 charging port and accepts up to 7.0kW on AC power, which means a full charge takes around 7.5 hours, perfect for overnight top-ups. Lexus also includes an at-home charging cable and second adapter cable as standard, which is a thoughtful touch.

In former times, as the Germans say, a ‘450' on the boot indicated V8 power. In the W116 S-Class era it was one of the world's most evocative badges when ‘SEL' was also attached.

As mentioned earlier, though, it's the M256 3.0-litre turbo-petrol with a 48-volt ‘mild hybrid' electrical system that's doing the driving, to all four wheels. The real V8 W223 will probably surface later this year or in early 2022 with the S580L flagship. Bring it on.

This is not to say that S450 isn't good enough. With that electrified assistance, the blown straight six is smooth and swift off the line and rapid as the auto seamlessly steps up through all nine gears. Because it's so hushed and refined, it doesn't feel 5.1s to 100 clicks quick, but watching the speedo says otherwise – acceleration is assertive and strong right up way past the legal speed limit.

All that's missing is the burbling soundtrack of a classic Benz bent-eight. Oh well. Outstanding economy is a price we're literally willing to pay in lieu.

Even more impressive is the S450's ability to hustle along mountain roads like an overgrown sports sedan.

Now, for Australia, all S-Classes are fitted standard with an adaptive ‘Airmatic' air-suspension set-up, including air springs and self-levelling tech. In Comfort up to 60km/h, the ride height can be raised by 30mm, or lowered by 10mm under the standard 130mm baseline in Sport at any velocity, while in Sport+ it falls another 17mm.

With that in mind, yes, the standard air suspension performs a magnificent job smothering out most surface imperfections around town. Yet its real other party trick is to tighten up the chassis when corners get interesting and Sport mode is selected. Aided by progressively weighted and reassuringly responsive steering, the Mercedes tips into turns with precision and poise, slicing through with virtually no discernible body lean or understeer.

Now, we're not talking a leisurely drive on rural highways here, but Healesville's famous Chum Creek Road, where even a Porsche Cayman would feel like it's had a strenuous dynamic workout. The S-Class can be hurried along with confidence and finesse, displaying outstanding handling and roadholding for a 5.2-metre long limo. And the fact that the ride quality only suffers marginally when the red horns are out is all the more remarkable.

Back in the cut-and-thrust of inner-city peak-hour traffic, the Benz in Comfort mode continued to reveal its driver-orientated yet passenger-focused twin-personalities, zipping in and out of gaps while remaining comfy and composed inside.

Only when parking in tight spots are you truly aware that the W223 is longer than a Mazda CX-9. The optional four-wheel-steering system is claimed to slash the turning circle to A-Class hatchback levels. 10.9 metres is the claim.

The 2021 S-Class never ceases to amaze and delight.

The RX450h+ delivers power that’s pert and prompt, with genuine bursts of acceleration that make driving fun. It’s always ready to go and there's no lag in stop-start traffic - which gives it a lively, dynamic feel around town.

The transition between petrol and electric power is seamless; you hardly notice the switch, which makes for a smooth, refined driving experience. The cabin is impressively quiet, even on the highway, making long trips comfortable and peaceful.

Regenerative braking isn’t adjustable and is subtle enough that many won’t notice it which is likely a plus for fans of traditional internal combustion engines who are making the PHEV leap.

The adaptive variable suspension adds a sporty edge to handling, letting you confidently take corners at speed. There’s some body roll but the RX never feels top-heavy or unsettled.

The steering carries the weight of the SUV but remains well-balanced and responsive. Overall, it’s a well-tuned machine that’s a pleasure to drive.

Maneuverability is a strong suit, too, thanks to a tight 11.8-metre turning circle and a clear, easy-to-use 360-degree camera system. Parking is easy-as-pie, which a lot of drivers will appreciate.

The RX earned a maximum five-star ANCAP safety rating in 2022, scoring highly across all protection categories: 90 per cent for adult protection, 89 per cent for child protection, 89 per cent for vulnerable road users, and 93 per cent for safety assist systems.

Standard safety gear includes eight airbags (dual front, front side, curtains, front centre, and driver’s knee) plus a comprehensive suite of driver aids. Standout features include emergency call functionality, child detection alert, side exit assist, front and rear collision warnings, park assist and emergency steering assist.

Additional tech covers blind-spot monitoring, driver attention monitoring, tyre pressure monitoring, daytime running lights, LED cornering lights, rear cross-traffic alert, lane departure alert, lane keeping assist, traffic sign recognition, and intelligent seatbelt warnings for the front two rows.

Visibility and parking are enhanced by a 360-degree camera system and front/rear parking sensors, while adaptive cruise control adds comfort on longer drives.

The rear seats have two ISOFIX mounts plus three top tether anchors, accommodating child seats safely. Autonomous emergency braking is active from 5.0 to 80km/h for pedestrians, cyclists, and backover and up to 180 km/h for cars.

Unlike many luxury brands that persist with a sub-par three-year warranty, Mercedes-Benz offers a five-year/unlimited kilometre warranty.

Intervals are every year or 25,000km, with a capped price service plan starting at $800 for the first year, $1200 for the second year and $1400 for the third year, totalling $3400. Alternatively, there is a Service Plan starting at $2700 for the first three years (saving $700 from the normal capped-price service plan), $3600 for four years and $5400 for five years.

The RX comes with a five-year, unlimited-kilometre warranty, which matches its key rivals but isn’t exactly class-leading by today’s standards.

Servicing is handled via a capped-price program, with each service costing $695. The intervals are well spaced at every 12 months or 15,000km, whichever comes first.

This Sports Luxury grade also includes a three-year complimentary 'Lexus Encore' membership, granting access to a handy phone app and member benefits at partners like Westfield and Ampol. On top of that, you get 24/7 roadside assistance for added peace of mind.