Lexus RX350H vs Mercedes-Benz C43

What's the difference?

It’s hard to look past the value equation of the RX350h Luxury 2WD when comparing it to almost all its competitors. The pricing is on point, but there are some features missing.

However, there are very few (if any) rivals with a true hybrid powertrain (sorry, mild hybrids do not count), so the RX will capture buyers looking for environmental credentials and efficiency without going full EV.

The drive experience is much better than before and it’s all wrapped up in a very stylish package. The Lexus RX should not be ignored.

The new AMG C 43 may lack the drama and excitement we’ve come to expect from the German performance brand, but that doesn’t mean it’s a bad car. Yes, it could be more extroverted and the ride could be improved, but this is still a sharp-looking sports sedan with loads of punch.

This is a car that speaks to its times, with ever-stricter emissions regulations making it harder and harder for car companies to produce loud, wild and charismatic cars. So Mercedes-AMG has worked within those boundaries and come up with a car that retains at least some of those core elements that has made the brand so desirable over the years.

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

Across its five generations, the RX has held significant visual appeal - especially the still-handsome second-gen version that was the first RX sold Down Under. The first-gen model skipped Australia.

The new model that launched in 2023 is a clear evolution of the car that came before, but it’s been softened and sharpened in the right areas, giving it one of the most appealing designs in its segment.

The proportions and design elements like the squat stance, unique C-pillar treatment, slimline headlights and nicely sloping roofline give it a sporty look.

In fact, I reckon it might be the best looking Lexus available today - not including the jaw-droppingly beautiful LC coupe and convertible, of course.

The interior is modern and feels like an evolution of Lexus’ previous cabin design - but elevated. The gloss black section of the dash helps here.

Levels built into the dash break up the bulk, but the interior is very grey. It could do with a dash of colour.

The synthetic leather seat trim doesn’t look premium. If you want a more expensive feeling RX, you need to pay more for a higher grade.

Mercedes has created something of a problem for itself with its decision to introduce AMG styling packages for the majority of its range, including the C-Class.

It means the C 43 has to walk a fine line between looking like a unique AMG model, rather than just a C300 with a bodykit and not out-doing the C63.

To that end it has AMG’s now familiar grille with vertical bars, the unique and complex-looking 20-inch alloy rims and a small lip spoiler on the boot. But otherwise it is surprisingly understated for an AMG, lacking the more obvious and muscular stance of previous AMG offerings.

Inside, there’s a similar theme, with the typical Mercedes-Benz luxury appointments but with a sportier, AMG twist. The steering wheel is chunky and comes with AMG branding, metallic shift paddles and a pair of rotary dials/buttons that allow you to alter the various drive modes and settings.

The one on the right allows you to switch between the pre-set Comfort, Sport, Sport+ and Individual modes, while the one on the left can scroll between the various individual aspects to tailor the settings to the conditions.

In typical modern fashion the design is tech-laden, with a digital display for the instrument panel (that can be switched between various graphics) and a large, tablet-style central multimedia touchscreen that controls the majority of the car’s non-driving functions.

The RX is a five-seat only proposition in this generation - the previous model had a seven-seat option - so if you need a third row you can look at the Lexus LM people mover or massive LX 4x4 SUV, or at any number of other three-row lux SUVs like the Volvo XC90 or new Mazda CX-90.

That doesn’t mean the cabin isn’t practical. 

Up front the seats offer excellent comfort levels and ample upper body support, but not a lot of hip support.

Lexus has changed up the door handles for the new RX and it can be complicated - initially.

The interior handles bamboozled every new person that got in my press car over the three week loan. But once you realise it’s a simple push of the thumb on the handle’s thumbpad and a gentle push, it all makes sense.

Lexus calls the electrically activated door handles an ‘e-latch’. Is it tech for tech’s sake? Probably. 

I recently reviewed the Lexus LM and commented on how much I like Lexus steering wheels and that’s true of the RX, too.

It has clearly identifiable controls and feels nice in your hands. Thankfully, the cruise control buttons are housed on the wheel too, so no annoying stalk on the wheel.

There’s plenty of space across the front row so you should avoid the awkward driver-passenger elbow bump on the centre armrest.

Under the armrest is a huge central bin that opens on the driver and passenger side. There’s also a big covered storage nook forward of the shifter and another ledge above that, as well as a sizeable glove box. 

The doors have ample storage room for bottles, but the space is almost too wide. My bottle slid around when driving so I had to lay it down.

The centre console houses two big cupholders with adjustable depth in one of them. Clever touches like this and the central bin add to the appeal.

As with the Lexus LM, I am a fan of the new Lexus multimedia set-up. It has an easy-to-navigate menu along the side, easy wireless Apple CarPlay connection, and visually appealing graphics.

It’s a world away from Lexus’ previous system. That frustrating touchpad is, thankfully, in the bin.

I quite like the gear shifter with its unusual gate and even the indicator feels and sounds premium.

Small rear windows make for a rear three quarter blind spot, but visibility is otherwise good.

On a side note, the RX has very strong air conditioning - perfect for an Australian summer.

Jumping into the second row, there’s plenty of space all around and no shortage of head, leg, knee and shoulder room. Although foot room under the front seats is tight.

As with the front seats, the rear row offers comfortable seating. Kids should be happy back there.

There’s only a small transmission tunnel so middle-seat legroom is good. And in great news for passengers, the rear backrests recline. 

Lowering the 40/20/40 split-fold rear seats for more cargo space is done via a lever on the side of the outboard seats, or by a button in the boot area. There are ISOFIX clips on the two outboard seats.

Other amenities in the second row include map pockets, two USB-C ports, knee-level air vents, climate control, and a pull-down armrest with pop-open cupholders.

Open the power tailgate and you’ll find cargo space of 612 litres with all seats in place, or 1678L with the second row stowed.

That’s a decent amount of space but not class leading. The Mercedes-Benz GLE has 630L and the VW Touareg can swallow 810L.

There’s no under-floor storage because that’s where some hybrid hardware is housed. You will find audio speakers, nice carpet, a cargo blind, two 4.0kg hooks and three top tethers. No spare, only a tyre repair kit.

The new C-Class has grown slightly in size compared to the model it replaces, most notably with a 26mm increase in the wheelbase which you can feel in the cabin.

The front seat space is good, with excellent adjustability for the power-adjustable seats and steering column. I had no trouble finding my ideal seating position which makes for a more enjoyable and uncompromised driving experience.

Rear space is a bit tighter (which is typical for this segment/size of vehicle), but thankfully the standard seats do have very deep sculpting in the backs which allow for more knee space and foot room.

However, at approximately 180cm (six-foot), I wouldn’t like to sit behind my seating position for long periods as my knees were touching the seat back, and headroom is compromised with the panoramic glass roof.

In terms of small item storage there’s a lidded console box in between the front seats as well as a pair of cupholders and a small tray where you can place your mobile phone.

It’s worth noting, though, that early examples of the C 43 in Australia do not have a wireless smartphone charging pad, with that reportedly being introduced from February production.

While that’s good news, it’s not really competitive in this day and age to offer a car costing six-figures without such technology.

There’s also only a single USB-C power outlet in the front, which is another disappointment, but there is a pair in the back.

Mercedes does win some points back for a respectable 455-litre boot, which has a nice wide load opening that will make packing luggage easier.

We’ll get to the major change under the bonnet shortly, but another significant alteration for this latest C 43 is the price.

It now starts at $134,900 (plus on-road costs), which pushes it well above its market rivals, the BMW M340i xDrive and Audi S4, which start at $104,900 and $106,200, respectively.

However, Mercedes has added more technology under the bonnet and loaded the C 43 up with standard equipment, including its '4Matic' all-wheel drive system, adaptive damping, rear-wheel steering and 20-inch alloy wheels.

In terms of creature comforts, the C 43 is well-appointed, with leather upholstery, a head-up display, augmented reality navigation, a panoramic sliding sunroof, and a Burmester 3D surround sound system.

There are two option packages for the C 43. The 'Digital Light Package' costs $2400 and adds Multibeam LED headlights with 'Ultra Range' highbeam, 'Adaptive Highbeam Assist Plus' as well as active light function and cornering light function.

The 'Performance Ergonomics Package' includes AMG Performance front seats, an AMG Performance steering wheel in Nappa leather and microfibre and the 'AMG Track Pace' system for an additional $5200.

Powering the RX350h is a series parallel hybrid system consisting of a naturally aspirated 2.5-litre four-cylinder petrol engine, a front-mounted motor and a nickel-metal hydride battery. 

Lexus doesn’t provide combined torque outputs for the hybrid, but total power for the system is pegged at 184kW.

This drives the front wheels only via a continuously variable transmission (CVT).

The biggest talking point about this new car is the engine, with AMG downsizing from the old C 43’s six-cylinder to a 2.0-litre four-cylinder turbocharged petrol engine.

But it’s not just any turbocharged four-pot, because it is fitted with technology that Mercedes claims has been inspired directly from its Formula One team.

While the F1 team engine facility is based in England, this engine was designed and developed by the Mercedes-AMG team at its Affalterbach headquarters, but the concept of the electric turbocharger reportedly comes from the engine that powered Lewis Hamilton to multiple world championships.

The electric exhaust gas turbocharger - to give it its official name - uses a small electric motor on the turbocharger shaft to spin up the blades without having to wait for any exhaust gases to pass through it first.

To power the electric turbo the C 43 is equipped with a mild-hybrid 48-volt electrical system.

Mercedes claims this means reduced lag and improved throttle response for a sportier driving experience. 

It also helps make this small engine produce big amounts of performance, with AMG extracting 300kW of power and 500Nm of torque from this 2.0-litre, which is more power than the previous six-cylinder C 43 managed.

The engine is paired to a nine-speed multi-clutch transmission, which isn’t a dual-clutch with a pair of clutches operating on every second gear ratio, but instead uses a “wet start-off clutch” for better take-offs and smoother shifting on the move (at least in theory).

Power is sent to the road via all four wheels thanks to Mercedes’ 4Matic all-wheel drive system.

The official combined cycle fuel consumption figure for the RX350h 2WD is 5.0 litres per 100 kilometres, with CO2 emissions of 114g/km. You won’t get figures like that in a petrol or diesel competitor.

Over three weeks of mixed city, country, urban and freeway driving, I recorded 6.8L/100km which is not too bad given some of my spirited driving. The trip computer said 7.0L which is close to my figure.

The RX350h takes premium unleaded petrol and has a 65-litre fuel tank, so expect a range of around 950km based on our real-world consumption number.

Despite the smaller engine you can hardly call the C 43 miserly, with a claimed combined urban/highway cycle rating of 9.1-litres per 100km. That’s only a 0.2L/100km improvement over the old six-cylinder.

On test, which included a return trip from Sydney to Bathurst via motorways and some dynamic back road driving, we saw a return of 11.8L/100km on the car's onboard computer.

While hardly hybrid-worrying, it’s impressive to think that driven modestly, such a potent engine can return a single-digit fuel figure.

The old RX was competent and even nice to drive but not a patch on the likes of the BMW X5. The new-gen RX improves on that in a big way.

It offers solid acceleration from a standing start. Lexus says 8.1sec from 0-100km/h - without giving you chills. The sportiest RX is the 500h Performance hybrid and that covers the same distance in 6.2sec.

The transition from electric power to petrol propulsion is more evident in this model than it was in the LM350h people mover I tested recently - the RX is a little noisier. The CVT doesn’t help this, offering up an uninspiring engine note.

It is, however, a much more fun car to push into tight bends than the previous RX. It remains reasonably flat in corners, and pulls out of tem with ease, but can’t compare to the dynamics of the dearly departed IS sedan.

The 19-inch tyres have large sidewalls and as a result soak up harsh bumps on the road. The non-adaptive suspension is tuned for better dynamism, meaning the ride quality is on the firm side.

The front-wheel drive RX lost traction for a second on a sweeping uphill section of my drive route, but the electronic traction systems otherwise kept the big SUV in check. 

But around town in urban areas, there is very little to complain about behind the wheel of the RX350h.

Let’s start with the good news. The new Mercedes-AMG C 43 is a quick car. The engine may be small in size but the electric turbocharger does its thing and provides plenty of punch.

You can get a performance boost, too, thanks to the belt-driven starter generator, which acts as a mild hybrid and gives you a surge of 10kW for a brief period if you need a sudden burst of extra speed.

The chassis is well-sorted, too, at least from a dynamic point-of-view. The rear-wheel steering can provide up to 2.5 degrees of turning, which improves handling at speed and manoeuvrability when parking.

However, there are some less-impressive elements to the C 43, too. The obvious one is the drama, or rather the lack thereof.

As I said at the beginning, the C 43 has never been as wild or raucous as the V8-powered C 63, but when you buy an AMG there’s a rightful expectation that it will provide some thrills.

The C 43 simply doesn’t have that character about it. Yes, it’s fast, but it produces that speed with efficiency rather than excitement.

And it’s not an engine size problem, because even the 2.0-litre four-cylinder A 35 and CLA 35 offer more ‘wow factor’ than the C 43.

Yes, the engine makes noise under acceleration (and it can be altered between discreet and sporty) but even at its best it sounds muted and lacks the evocative tone of a V8 or six-cylinder engine. 

Another disappointment is the transmission calibration, with the gearbox awkwardly shifting out of first gear on multiple occasions during our test drive.

In the taller gears it felt smooth enough cruising along, but given its low speed shifts we’d like to spend more time in the urban environment before passing final judgement. 

The other notable element of the driving experience we struggled with was the ride quality. While fine on the smoother motorways, our test drive included time on some patchy country back roads and the C 43, even in the ‘Comfort’ suspension setting, was simply too firm.

Riding on low profile tyres, the adaptive dampers struggled to isolate the cabin from the imperfections in the road, leading to a fussy ride at times.

Overall the C 43 is a good car, but it feels like there are still some areas where Mercedes could improve it to make it really live up to the AMG badge.

The C43 gets a comprehensive list of safety equipment that leaves little out. Obviously there are the usual passive safety items, like 10 airbags, including dual-front combined pelvic/thorax airbags and a front centre bag that drops between the front seat passengers to minimise the chances of a head clash.

Also included as standard is autonomous emergency braking front and rear (covering speeds between 7.0-200km/h), adaptive cruise control with active stop/go, a 360-degree parking camera, 'Active Parking Assist', 'Active Lane Keeping Assist', 'Blind Spot Assist' and, of course, anti-lock brakes with 'Brake Assist' and 'Adaptive Brakes' with Hold function and electronic stability control.

Also included are dusk-sensing LED lights, rain-sensing wipers and run-flat tyres with tyre pressure warning.

The C43 also comes equipped with Mercedes’ 'Driving Assistance Package Plus', which adds even more safety gear. This includes 'Active Blind Spot Assist', 'Active Brake Assist with Cross-Traffic Function', 'Active Emergency Stop Assist', 'Active Lane Change Assist', 'Active Lane Keeping Assist', 'Active Steering Assist', and 'Active Stop-and-Go Assist'.

While the C43 hasn’t been specifically crash-tested, the latest C-Class was rated by ANCAP with a five-star score for all models except the upcoming C 63 S E Performance.

The RX350h is covered by a five-year, unlimited-kilometre warranty, and the servicing schedule is every 12 months or 15,000km.

There’s a capped-price servicing plan lasting five years and it will cost $695 per service. That's significantly less than some rivals like the Mercedes GLE.

The RX is covered by the 'Lexus Encore' loyalty program and includes complimentary service loan cars, fuel offers as well as discounts and other offers with Lexus partners.

The C 43 is covered by Mercedes’ five-year, unlimited kilometre warranty, which has become the new standard for the luxury car market.

Service intervals for the car are at 12 months/25,000km, which is on par with industry standard.

Mercedes-Benz Australia will offer a service plan for the C 43, prices were yet to be confirmed at the time of publication but the company has indicated it will be similar to the C300. 

That means $550 for year one, $900 for year two, the third service costs $1000 and the fourth year service costs $2450 - for a total of $4900 for the first four years of ownership.