Mercedes-Benz SL63 vs Lexus LC500

What's the difference?

The new Mercedes-AMG SL63 4Matic+ is guaranteed to turn heads for decades to come. But there’s enormous design and engineering substance underpinning this car’s undoubted good looks. Stunning performance, superb dynamics and top-shelf safety make this a powerhouse GT to be reckoned with.

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

Stunning to behold, and even more so to listen to, the LC 500 Convertible with no doubt turn as many heads as its owners surely want it to. It's not the final word in performance, but it's a lavishly equipped transporter none the less.

Rather than a strict two-seater, this time around the SL adds the flexibility of ‘+2’ rear seating while the previous 'Vario’ folding hardtop has been binned, the new car returning to a traditional, electrically-folding and weight-saving (-21kg) soft top. 

Mercedes-Benz design chief Gorden Wagener started the new model’s development from a ‘clean sheet’ and Mercedes-AMG says “not a single component comes from the predecessor SL, or any other model such as the AMG GT Roadsters”. 

Always a subjective call, but I think this car’s proportions are just about perfect. The lengthy bonnet with its twin longitudinal ‘Power Domes’, raked windscreen and fat haunches create a wide stance and presence that’s almost impossible to ignore.

Aggression, as with the sinister headlights and 21-inch rims, is subtly combined with soft curves along the flanks and around the rear. Note the seamless door handles.

And it’s not all about aesthetics. Active aero has been integrated into the front apron and retractable rear spoiler. Plus the ‘Z-fold’ roof design does away with the need for a separate cover.

The interior is sub-zero cool with slick screens, an 11.9-inch display covering multimedia and a 12.3-inch unit for instrumentation ahead of the driver, being particular highlights.

Turbine-style air-vents at the leading edge of the split-level dash and alloy trim elements are a tip-of-the-hat to SLs past and the deft mix of large flat surfaces with complex curves oozes design confidence.

It’s eye-catching, the LC 500, if big, bolshy convertibles are your thing, and especially viewed front-on, where the aggressive nose design ends in a sharp crease in the mesh grille. I love the headlight design, too, which bleeds back into the body work, but also merges with the vertical light cluster that bookends the grille. 

The side view is all shining alloys and sharp body creases, too, leading to an oversized boot that stores the fabric, aluminium and magnesium roof structure, which drops or raises in 15 seconds at speeds of up to 50km/h. The design fits into what Lexus calls an “impossibly small space behind the seats”.

Inside, it’s a snug but luxurious space, wrapped largely in leather and equipped with a wealth of technology. It’s a point we’ve made before, but why Lexus perseveres with its trackpad infotainment control technology is beyond us, but there’s no denying the cabin of the LC 500 is a wondrous place to spend time. 

We particularly like the integration of the centre screen, which is recessed beneath the leather-wrapped edge of the dash. While some look like an afterthought, this appears to have been included in the broader design philosophy.

In the context of a high-performance GT, practicality is pretty impressive.

At just over 4.7m long the SL is a sizeable machine and much of its lengthy (2700mm) wheelbase is devoted to making the driver and front passenger comfortable.

There’s plenty of space for that pairing and just enough storage to cope with the ‘things’ they’ll typically bring with them.

Door pockets offer enough room for a few odds and ends, although you’ll struggle with even a medium-size bottle unless you’re willing to lay it down horizontally along the top of the aperture.

A handy lidded bin between the front seats doubles as a centre armrest, there are two cupholders under a sliding lid in the centre console and the glove box is a decent size. 

Power and connectivity options run to four USB-C ports, a 12-volt socket and the wireless device charging pad.

Then there are the rear ‘+2’ seats, and Mercedes makes no bones about the fact they’re intended for occasional use only, even suggesting a 1.5m occupant height limit.

And there’s no doubt they offer a handy emergency seat or a fun kids’ zone. Just ask a Porsche 911 Carrera owner how much this kind of seating arrangement increases a sports car’s flexibility.

At 183cm I gave the back seat a crack, which meant sliding the front (passenger) seat way forward with the backrest close to upright. But I squeezed in, and there was just enough legroom for a person in front at the same time. 

With the roof in place there’s the added pleasure of cranking your head over to around 45 degrees. But it’s do-able! 

No storage, adjustable ventilation, or power back there. But that’s fair enough, especially given there are USBs available in the front centre storage box.

Boot volume is 240 litres with the roof up and 213 litres with it folded, which is enough for some light luggage, and not too shabby when you think a Toyota Corolla hatch offers up just 217 litres (with all seats up).

There’s a 12V socket in there, but don’t bother looking for a spare, in the event of a flat your only option is a repair/inflator kit.

It’s not, really. But then, what were you expecting?

As mentioned above, the interior feels snug for upfront riders, but not in a bad way. More that elements of the interior feel like they’re reaching out to greet you, leaving you with the impression of being tucked into the cabin.

Backseat riders are out of luck, though, with the seats really only reserved for emergencies. Legroom is tight, and while Lexus promises the roofline is about on-par with the Coupe, it’s not going to be a comfortable journey.

The LC 500 Convertible stretches 4770mm in length, 1920mm in width and 1350mm in height, and it rides on a 2870mm wheelbase. It will sit four at a pinch, and provide 149 litres of luggage space.

There are two ISOFIX attachment points in each of the rear seats, as well as top-tether points.

It costs $214,000 - and that’s rather a lot of money - but unlike some premium and luxury cars, with Lexus, once you’ve handed over the cash, that’s it. There’s no tempting option list to lure you into parting with even more of your hard earned. 

And I mean that literally - Lexus proudly proclaims that “there is no option list” for the LC 500 Convertible, so suffice it to say it arrives with plenty of gear. 

Take a deep breath…

You get 21-inch two tone alloys, triple-stack LED headlights, keyless entry, retractable door handles and rain-sensing wipers outside, while inside, you’ll find dual-zone climate, leather-accented seats which are heated and ventilated, neck-level heating for when the roof is down, a heated steering wheel and sports pedals. 

The tech stuff is handled by a 10.3-inch centre screen with Apple CarPlay, Android Auto and on-board navigation, both of which are controlled via Lexus’ impossible-to-kill touchpad. There’s a second, 8.0-inch screen for the driver, and the lot pairs with an impressive 13-speaker Mark Levinson stereo.

There’s also a heap of safety stuff, but we’ll come back to that in a moment.

If that’s not enough for you, you can spring for the Limited Edition, which is $234,000 for each of its 10 available examples. It arrives in a unique Structural Blue hue, with a white leather interior with blue highlights. It is designed to be the most blue of blues, too, with Lexus saying the paint colour was the result of a 15-year research project. Which sounds like a thrilling way to spend a decade and a half.

This new ‘4Matic’ all-wheel-drive SL63 features AMG’s (M177) 4.0-litre twin-turbo V8, superseding the previous rear-wheel-drive SL’s similarly configured 5.5-litre unit.

Hand built by one AMG technician from start to finish, it produces 430kW (around 580hp) from 5500-6500rpm and 800Nm across a broad plateau from 2500-5000rpm.

It’s something of a mechanical masterpiece, and the previous seven-speed auto transmission, driving the rear wheels only, has been replaced by a nine-speed dual-clutch auto (with wet multi-disc start-off clutch) sending drive to all four wheels via Merc’s ‘4Matic’ AWD system.

It’s a lusty power plant, this one, and not something you immediately expect to find in a luxurious Lexus convertible.

The 5.0-litre V8 produces 351kW and 540Nm - 260kW of which arrives from 2000rpm - and it sounds like a God of Thunder as it’s doing it. 

It pairs with a 10-speed automatic and sends all that grunt to the rear tyres, with Lexus’ Active Cornering Assist and a mechanical limited-slip differential helping you to not make a mess of things when tackling corners. 

Mercedes-AMG’s official fuel economy number for the SL63 on the combined (WLTP) cycle is 13.9L/100km, the 4.0-litre twin-turbo V8 emitting 319g/km of CO2 in the process.

On the roughly 300km launch program we covered urban, B-road and some freeway running, returning an (indicated) average of 17.5L/100km. And that reflects some enthusiastic driving along the way.

The fuel tank requires 70 litres of 98 RON premium unleaded to fill it which translates to a theoretical range of around 500km, dropping to 400km using our real-world number.

Remember when I said it was lusty V8? When has that ever been good news for fuel use?

Lexus reckons you’ll get 12.7L/100km on the combined cycle, but the temptation of all that grunt will pretty much ensure that never happens. Emissions are pegged at 290g/km of C02.

The LC 500 Convertible’s 82-litre fuel tank only accepts 98RON fuel.

I recall driving the AMG SL65 around the backroads of Tassie a few years ago and that twin-turbo V12 monster famously packed 1000Nm of torque, while this car ‘only’ has 800.

But there comes a point where enough is enough… and this is enough!

With maximum torque available from 2500-5000rpm and peak power (430kW) on call from 5500-6500rpm there’s always stupendous acceleration available with a squeeze of your right foot.

Claimed 0-100km/h time is supercar fast at 3.6 seconds, while top speed is a toupe-troubling 315 km/h. And that’s electronically limited!

A typically ferocious engine noise and howling exhaust note accompany rapid progress and shifts from the nine-speed dual-clutch transmission are quick and positive, not to mention especially enjoyable using the steering wheel-mounted paddles.

There are six ‘AMG Dynamic Select’ drive programs from Comfort through to Race, the latter including a Drift Mode, which we didn’t experiment with. Nor did we dip into the ‘AMG Track Pace’ system for circuit-focused mapping and timing

However, far from drifting, the grippy Michelin Pilot Sport 4S rubber (275/35 fr - 305/30 rr) plants the car securely with the all-wheel-drive system and electronic locking rear diff playing their part.

I found the perfect set-up was in the ‘Individual’ mode with the engine, transmission and steering in racier settings and the suspension in ‘Comfort’. The adaptive damping in this configuration mixes smooth ride compliance with sharp dynamic response.

The car’s aluminium space frame chassis is part of a body structure mixing aluminium, magnesium, fibre composites and various strength steels.

Torsional rigidity is claimed to have been improved by 18 per cent and despite the lack of a roof the SL feels tight and solid.

Suspension is by alloy double wishbones front and rear with adaptive damping and active hydraulic anti-roll stabilisation standard (so, no physical anti-roll bars).

At the same time the 4Matic AWD system is able to vary torque distribution up to 100 per cent to the front or rear axle depending on where drive can be put to best use.

The speed sensitive, variable ratio, electronically controlled steering is accurate and turns in beautifully with good road feel. No doubt assisted by electric rear steering able to adjust the angle of the rear tyres by up to 2.5 degrees.

All this adds up to a hugely impressive package that, despite its 1970kg kerb weight, feels agile, athletic and able to attack corners like an overgrown hot hatch, putting its power down with unwavering authority.   

While indecently fast the SL63 can also stop rapidly with the AMG high-performance braking system standard. 

Huge composite ventilated and cross-drilled discs (390mm fr - 360mm rr) are clamped by six-piston fixed alloy calipers at the front and single-piston units at the rear. They wash off speed calmly and consistently with perfect pedal feel.

Even at highway speeds, particularly with the windows up, normal conversation is easy with the roof down. But if you need to raise (or lower) it, the operation takes 15 seconds and is possible up to 60km/h. 

Under the heading of miscellaneous observations, the turning circle is a not insubstantial 12.8m, so beware in the car park.

A front axle lift function is a welcome standard feature, raising the car’s nose 30mm with the press of a button. And lift locations are stored in GPS data, so the car will subsequently remember to lift itself at the same place, even if you don’t! 

Heating and cooling for the front seats combined with the heated steering wheel and Air Scarf neck warming makes winter top-down driving a pleasure.

The digital instrument display is not only crystal clear, it can be changed through multiple configurations, including a tunnel-like graphic for engine revs as well as specific readouts for speed, g-force, the lot.

At the same time, the central media screen’s angle can be adjusted to better cope with reflections and the windscreen wiper system Merc calls ‘Magic Vision Control’ channels fluid along the wiper arms onto the rubbers, which isn’t new, but works spectacularly well here.  

It’s a tough nut to immediately crack, the LC 500 Convertible.

It feels like it really wants to be a super-accomplished performance car, and on longer, more sweeping bends it is, with that thick flow of power ensuring you simply surf through corners before rocketing out the other side, the air filled with that growling exhaust note as your right foot finds its way to the carpet.

But on the tighter stuff, there are some factors that play against it. The suspension feels sorted and that engine is always willing to deliver, but for mine, the steering and brakes felt a little disconnected from the experience, not inspiring much in the way of late-braking confidence. And then there’s the sheer two-tonne-plus weight of the thing, which can’t be totally hidden, even by Lexus’ best wizardry.

Don’t get me wrong, it’s very capable, even on surprisingly tight stuff. It’s just that there’s something of a disconnect between car and driver. 

That’s not a bad thing, really. Are you really buying a premium convertible to attack a mountain pass? Probably not. And keep it flowing through corners and the LC 500 Convertible will keep a smile painted on your face, owing mostly to wave of torque you can ride to your destination. 

Hovering your foot over the accelerator must surely be what the President feels like whenever he stands near the nuclear football, with that big V8 always ready to turn on the fireworks. 

Away from the red mist, you’ll find the LC 500 Convertible positively flows from destination to destination, the 10-speed gearbox - which can feel flustered at pace - seamlessly flicking through its options, and the ride in its most comfortable settings disposing of most road imperfections before they enter the cabin. 

The cabin is also very cleverly insulated, not just when the four-part roof is up, but also when it’s down, with the climate and ambience of the interior largely unaffected by what’s going on in the outside world.

The Lexus LC 500 Convertible arrives with six airbags, a reversing camera with guide lines, parking sensors, and the usual suite of traction and braking aids, but there’s much more to the safety story, too. 

The more high-tech stuff includes parking sensors, pre-collision assist with AEB, lane keep assist, blind-spot monitoring, rear cross-traffic alert and active cruise, as well as bespoke convertible safety gear, like active roll bars that deploy when the car is in danger of rolling over, protecting the occupants beneath that soft roof.

The SL63 4Matic+ will be covered by Mercedes-AMG’s five-year/unlimited km warranty, with roadside and accident assistance included for the duration, both of which are expected in this category. 

Maintenance intervals are 12 months/20,000km, and a fixed-price service plan lists an average of $1583 for each of the first three visits to the workshop. Not exactly small change, but not unheard of in this part of the market.

Lexus vehicles are covered by a four-year, 100,000 kilometre warranty, and the LC 500 Convertible requires servicing every 15,000kms. 

Lexus's Encore ownership program includes pick-up and drop-off servicing, but the new Encore Platinum level for owners of its more exclusive models unlocks even more stuff.

One is a new On Demand service, which allows owners to book a different style of car when heading off on a holiday or business trip. The loans are available in your state or somewhere else in Australia if you're travelling, with your car waiting for you at Qantas Valet for you when you arrive.

The On Demand service is available on four occasions over your first three years of ownership (which is also the length of the Encore Platinum membership).