Mercedes-Benz C350 vs Lexus Rx450H+

What's the difference?

Baby steps these might be, but they're important ones for Benz. The new in-cabin tech and clever engine in the cheapest models only strengthen the C-Class proposition, without taking anything away from the drive experience, cabin ambiance and utterly sublime ride.

In short, Mercedes' reign at the top of the premium mid-size segment is unlikely to be toppled anytime soon.

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.

Perhaps not quite blink and you’ll miss them, but we're not talking radical changes either, folks. Benz tells us as much as 50 per cent of the C-Class components are new or changed, but it has clearly subscribed to the 'if it ain’t broke' philosophy in the design department.

Yes, there are new bumpers front and rear, new LED light configurations and new colours and wheel designs, but we’re not talking huge changes outside. Still, the C-Class cuts a fine figure on the road, what with its intricate alloys, bonnet-defining grille and simple, understated body contours. Australia will take every available body style, too, including sedan, coupe, cabriolet and - our personal favourite - the 'estate' station wagon.

The C 43 AMG now gets the twin-blade grille design used on the V8-powered models, as well as a two pairs of rounded exhaust tips at the rear.

Inside, though, the changes are more substantial. For one, the new-generation Mercedes Touch Control steering wheel arrives as standard, as does a new and very effective 12.3-inch screen that replaces the traditional dials in the instrument cluster (standard on every model). 

The cabin remains a peaceful and premium-feeling space, with a fine use of materials (including quilted leather on the door panels, polished silver or faux-wood for the centre console and leather for the steering wheel), and Benz deserves credit for ensuring that sense of luxury extends to backseat riders. 

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.

It all depends, really. All C-Class variants sit on the same 2840mm wheelbase, and stretch 1810mm in width. The sedan, coupe and cabriolet versions measure 4686mm in length, while the Estate’s bigger cargo area increases its size to 4702mm.

Predictably, then, the estate offers the most useable (VDA) boot space, with 490 litres with the rear seats in place, swelling to 1510 litres with the rear seats folded flat. The sedan version is next on the cargo-carrying list, with 455 litres, followed by the 380 litres of the coupe and 285 litres of the cabriolet.

We spent our entire time in the four-door sedan models, and we can report a spacious and comfortable space for driver and passenger (you could play ping pong on the wide centre console) with two cupholders and room in each of the front doors for bottles. There’s all the USB and power connections you might need (most housed in a deep storage bin that separates the front seats) and the more expensive models offer wireless charging for compatible phones, too.

Climb into the sedan’s back seat, and you’ll find impressive legroom (behind my own 176cm driving position), but headroom - especially in sunroof-equipped cars - feels a little tighter. The rear seat is actually wide enough to fit three adults at a pinch, but the tall and bulky tunnel absolutely obliterates leg room for the middle-seat rider.

There are two cupholders in the pulldown divider that separates the backseat, as well two ISOFIX attachment points. Rear occupants also get there own air vents, as well as a 12-volt power source.

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.

It’s here where the C-Class is at its most updated, serving up a new turbocharged 1.5-litre hybrid engine in the entry-level C200. Alone, it’s good for 135kW/280Nm, but it’s combined with a clever 48-volt system that adds up to 11kW of bonus power low in the rev range, happily plugging the power void usually left by turbo lag when taking off, or if you plant your foot when overtaking.

The C300 is powered by a more conventional 2.0-litre, four-cylinder good for 190kW/370Nm, while the sole diesel (in the C220d) is a four-cylinder unit that produces 143kW/400Nm. All are paired with a nine-speed automatic transmission.

The C 43 4Matic's engine remains a fabulous thing, only now tweaked for a little bit more power. It's good for 287kW/520Nm, and is paired with a nine-speed transmission that sends the power to all four wheels, albeit with a bias toward the rear tyres.

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.

Let’s start with the C200, where the addition of the clever hybrid system has helped drop fuel use to a claimed 6.0-6.3 litres per hundred kilometres. The old car delivered 6.5 per hundred, but was slightly quicker from 0-100km/h (7.2sec- 7.7sec). 

The C300 will sip a claimed 6.5-6.9L/100km on the same cycle, while the diesel requires a miserly 4.7 litres. The C 43 is the thirstiest, of course, needing 9.1-9.3L/100km on the same cycle. 

The C200 makes do with a 41-litre tank (as does the diesel) while the C300 steps that up to a 66-litre tank. And all those numbers related to the sedan body shape, so expect some slight variations if you’re shopping for a coupe cabriolet or estate.

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.

Keen to sample the new hybrid tech in the C200, we made a beeline for the cheapest C-Class. And if you’d told me, even a handful of years ago, that a piddly 1.5-litre engine would be enough to drag the 1555kg Benz around, I’d have labelled you crazier than Donald Trump's Twitter account. 

The C200’s system is a unique hybrid set-up, in the sense that it only delivers extra power in the tiniest of circumstances, but they’re the areas that it really needs it. From a standstill, the electric motor delivers its extra 11kW of oomph at just the right moment need to help get you moving (the same when overtaking) and it does genuinely make a difference. 

It can’t completely overrule the concrete laws of physics, though. Plant your foot on anything that even looks like a hill and you can definitely hear that 1.5-litre engine working hard - interrupting the ambience of the cabin - but keep it in the sweet-spot of the rev range and it’s a quiet, capable-feeling engine that delivers more punch than its size might suggest.

On Germany’s epic autobahns, the needle even sailed past 215km/h without too much encouragement (even if I could have knitted a sweater in time it took to to close the last 10-or-so-kilometres). Is that relevant for Australia? Sadly not, but it does suggest the engine is more capable than we will ever need it to be.

Elsewhere, the not-too-different C-Class rides an absolute dream, smooth-sailing over bumps and road imperfections, and the cabin is serene and comfortable - though there was more wind noise at times than I was expecting.

Downsides? Well, the cheapest C-Class doesn’t feel the most dynamic offering, with the light steering serving up a slight disconnect between the steering wheel and the road below in its most comfortable settings. Switching to Sport improves matters, but if you’re life is mostly city and suburbs, it will matter little.

The nine-speed transmission can behave oddly at times, too; smooth and lightning fast as it climbs the gears, and mostly perfect on the way back down. But I noticed a definite thump occasionally as it shifted down from second to first gear, which stripped a little refinement from the drive experience.

It's more noticeable in the C 43 4Matic AMG, but it's vastly overshadowed by the thick and meaty power delivery from that stonking turbocharged engine. It's a rocket, and while it's not as fast or as loud as its C 63 big brother, I honestly think the tweaked C 43 is all the AMG I'd ever need.

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.

While specific maintenance pricing is yet to be confirmed, each of these models is covered by three-year warranty, with service intervals pegged at 25,000km or 12 months.

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.