New Mercedes-AMG SL or Lexus LC Convertible

The contenders

New Mercedes-AMG SL 55 4Matic+ Premium Plus

List price £147,475
Target price £147,475

This seventh-generation SL promises to be more of a sports car than its predecessors, but is that the right approach for a high-priced convertible like this?

Lexus LC Convertible 500 Sport Pack Plus

List price £108,395
Target price £105,679

The LC is one of our favourite luxury convertibles, thanks to its impressive blend of comfort, refinement and performance. In other words, it will be hard to beat

Iconic. It must be one of the most overused adjectives in motoring, used to describe everything from brands, racetracks and cars, to storied industry executives. But when it comes to the Mercedes SL we dare you to find a more appropriate term. As former Mercedes boss Dieter Zetsche once remarked, “There are around 900 million cars in the world, and thousands of models, but there are only a handful of automotive icons. Our SL is one of them.”

That’s because the SL has always done things a little differently. It has never been a hardcore sports car like the Porsche 911 nor has it tried to be a laid-back luxury car like a Rolls-Royce Dawn – it incorporates aspects of both in a nuanced ‘grand touring’ role. Which makes the all-new SL a bold step by Mercedes because, unlike its predecessor, this seventh-generation model is the first SL to be developed by the in-house AMG performance division – hence the car’s new nomenclature: Mercedes-AMG SL.

Out goes the heavy folding metal roof, with a lighter fabric top brought back instead, while the all-new aluminium underpinnings are likely to be shared with the next Mercedes-AMG supercar. Rear seats have been reinstated to improve usability, and for the first time the SL comes with four-wheel drive (to improve traction) and four-wheel steering (to improve agility). In other words, the SL has a new game plan.

It can’t, however, give four-seat luxury convertibles such as the Lexus LC Convertible a free run by being too uncompromising. Indeed, the LC 500 was named ‘best for luxury’ in the convertible category at the latest What Car? Awards, thanks to its impressive blend of comfort, refinement and performance. It also comes with a beautiful interior and a sensational-sounding V8 engine, making its £108,395 price tag look like rather good value when you consider that it’s around £40,000 less than the equivalent SL55.

Driving 

Performance, ride, handling, refinement

Both cars are powered by V8 petrol engines, but the LC’s is more old-school, with a larger capacity (5.0 litres) and no turbochargers, while the SL’s 4.0-litre unit is boosted by twin turbos, giving it a power output of 469bhp to its rival’s 457bhp. Those numbers might sound quite close, but because the SL has the benefit of a clever launch control system and an inbuilt traction advantage courtesy of its four-wheel drive system, it decimates the LC in a drag race. The SL can storm from 0-60mph in just 3.7sec – a whole 1.4sec quicker than the rear-wheel-drive LC.

Once the LC manages to gain traction (admittedly our testing took place on a bitingly cold day), the gap in performance reduces, but from behind the wheel the SL still feels noticeably more responsive. This is in part because the SL’s engine delivers its maximum shove much lower in the rev range than the naturally aspirated LC, but also because Mercedes’ nine-speed automatic gearbox is quite a bit snappier than the 10-speed unit in the LC.

Ultimately, if you want to make quick progress in the LC, you need to rev it hard, but this feels a little at odds with its otherwise relaxed demeanour. Push on and you’ll certainly enjoy the charismatic howl that emanates from its twin exhausts – an engine note that we actually prefer to the theatrical but at times over the top soundtrack delivered by the SL – but it can feel rather languorous when making quick changes of direction, and its higher kerb weight means that it leans rather noticeably through corners.

This isn’t to say that the LC isn’t enjoyable on a country road, but it’s better suited to being driven at seven-tenths, rather than flat out. Which is where the SL comes in. In its most extreme Sport Plus mode, it does a convincing impression of a proper sports car, thanks to steering that has virtually no slack and a four-wheel steering system that makes it feel remarkably nimble for a car of its size. You can also carry an incredible amount of speed into corners, and as the forces build, the car just grips harder, with its adaptive suspension ensuring that body lean is almost non-existent.

But the most impressive thing about the Mercedes-AMG SL is its ability to engage one moment and pamper you the next. Knock the drive mode back to Comfort and it does a better job than the Lexus LC Convertible of rounding off bumps around town and is impressively cosseting on the motorway (whereas the LC tends to shudder and shake over large abrasions).

With their roofs up, our contenders are suitably quiet at motorway speeds, although the SL lets in a little more road noise (not helped by the fact that our test car appeared to have a wonky seal). The SL's clip-on wind deflector (which goes over the rear seats) also generates some noise when you're driving with the roof down, but it does a reasonable job of reducing buffeting inside the car. The LC – which comes with a glass wind deflector between the rear seats – provides a slightly calmer roof-down environment, though. 

Next: What are they like inside? >>

Page 1 of 5