Mercedes-Benz AMG GT vs Lexus LC500

What's the difference?

The GT63 4Matic+ is a breathtaking example of everything that Mercedes-Benz and AMG are.

Ferociously fast, incredibly agile and superbly sophisticated, it should be on anybody’s shortlist, if that also includes a Porsche, Aston Martin, Maserati or even a Lamborghini. And it’s definitely much more than yesterday’s SLC ever was – for similar money in today’s terms, as it turns out.

But, around Tasmania’s glorious roads at least, the Mercedes-AMG lacks the ride comfort and road noise isolation to be a fully-rounded-out GT, and that’s a disappointment for a brand with such formidable history in making such cars.

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.

This is still clearly a Mercedes AMG GT coupe, like the 2014 C190 original, but a ground-up redesign sees it subtly yet significantly altered.

Some 270kg heavier than before, the larger-in-every-dimension body combines aluminium, steel, magnesium and fibre composite materials for improved rigidity and a lower centre of gravity. Length (4729mm) and wheelbase (2700mm) have been stretched by 177mm and 70mm respectively. Width (1984mm) and height (1352mm) are also up.

The nose treatment is similar to before, especially with the bulgy bonnet and signature vertical slatted grille fitted. These, combined with the LED digital headlight shape effect, is reminiscent of, but far-better executed than, the goofy-looking MG5’s face.

Underneath, it's an all-new platform shared with the SL, with the rear transaxle of the old car replaced by a permanent AWD system, leading from 46:54 front/rear weight distribution to 50:50 as a result.

That aggressive, exaggerated cab-backward/ultra-long bonnet silhouette that visually connected it with the SLS gives way to more-conventional and practical coupe proportions that is striking if not especially original, since they do look quite 911-esque. Along with the longer wheelbase and wider tracks, the result allows for two small rear seats to be fitted, while liftback cargo access remains.

Similarly, in the name of way-more usable interior packaging, Mercedes-AMG says it pushed the driving position nearly 180mm forward compared to the previous GT. Let’s see what that all looks like inside.

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.

The first impression inside is that of space, despite the falling roofline and coupe-like upsweep of the side windows and you look back. While, again, similar to a 911s, a kink at the door gives the GT a unique character.

Even larger people will appreciate the generous amounts of room up front, with space to stretch, sat in sumptuously comfy bucket seats. Note that the standard ones are better than the racier but firmer Sports versions.

The driving position is perfect, ahead of a dashboard that is very typical modern Mercedes in appearance and layout.

To that end, the tablet-style integrated touchscreen (11.9 inches) is clear, fast and intuitive once time is taken to learn it. And points are also won for the multi-configurable electronic instrumentation, that allows for a variety of screens, including track, classic and minimalist views.

The trademark turbine air vents, the quite beautiful material and trim finishes and just the general solid feel are further typical contemporary Mercedes cabin treatments, as are the excellent ventilation and ample storage options.

And while rear vision isn't great, that's what cameras are for. It's all pretty much on brand.

It is a shame, given how elevated the Mercedes-AMG engineering is underneath, that the GT’s interior look and ambience is so similar to those of a (albeit higher-spec) C-Class or GLE. It's simply not as special as some of the company’s previous sports cars.

More annoyingly, the ride is too firm and bumpy for a GT, and this has the unhappy effect of provoking random rattly trim sounds within the cabin. It’s a bit like scrunched-up cellophane. In a $420K (as tested) Merc, that’s very disappointing, especially as it can be heard over the copious amount of road and tyre noise droning through, particularly on coarser bitumen surfaces.

Further back, the rear seat is strictly two-plus-two, and nobody over 150cm tall is recommended to travel there by Mercedes itself. That sloping roofline is the culprit. That said, brief trips with a bowed head are possible, as the fixed cushions and split-folding backrests are actually surprisingly comfy. But only for short journeys. Kids should love it though, and the second row does open up the GT’s usefulness enormously.

As does a near-doubling of the AMG’s cargo capacity, jumping 146 litres to 321L with backrests erect, to a whopping 675L (+325L) in two-seater mode. The flat floor is accessed via a large electrically-operated liftback door, offering quite a large aperture for easy loading/unloading.

Having no spare wheel helps here, with a tyre inflation kit included in lieu of that.

Meanwhile, at the front, under the bonnet, things have definitely changed for the better as well.

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.

There’s a plaque signifying which engineer “handcrafted” the GT’s engine – in this case, the famous M177 in 3982cc, 4.0-litre twin-turbo intercooled V8 petrol guise.

Delivering 430kW of power at 6500rpm and 800Nm of torque from 2500-4500rpm, it sends drive to all four wheels via a nine-speed multi-clutch transmission (dubbed MCT in AMG-speak), catapulting the GT63 4Matic+ from 0-100km/h in just 3.2 seconds, on the way to a top speed of 315km/h.

How does it do that?

With AWD, the GT is now nearly 15 per cent heavier than before, but it still manages a punchy 218kW/tonne. Active aerodynamics over, inside and under a more-rigid body structure also helps.

The AMG 4Matic+ AWD system goes from 50/50 front/rear, to 100 per cent rear, variable torque distribution according to conditions and settings, and backed up by an electronic limited-slip differential. Among the many driving settings are Race Start, Drift Mode and good-old Comfort, if it all becomes too much.

Also keeping all that performance in check is a high-performance composite brake setup with improved cooling for faster responses.

Interlinked active roll bars improve body control, the five-link independent suspension features adaptive dampers for a softer ride.

And, as for that 4WS tech, the rear wheels steer opposite to the fronts at up to 100km/h (by some 2.5 degrees) for tighter and tidier handling, or 0.7 degrees in the same direction above 100, for greater stability and road-holding.

Its effect on the way this near-two-tonne coupe zigs and zags around corners is something you need to experience to really appreciate.

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. 

Actually, the GT’s economy isn’t horrendous considering how fast it can go.

Even blasting a few times around beckoning country roads, we managed an indicated 13.0L/100km, which is an improvement on what Mercedes-AMG says the GT averages the 14.6L/100km average that Mercedes-AMG officially states.

That translates to a carbon dioxide emissions rating of 334g/km.

Using 98 RON premium unleaded petrol, an average of just under 480km between refills of the 70L tank is possible. The urban run sees consumption rocket to 21.8L/100km (for just 321km of range), or 10.4 out on the highway run, meaning that over 670km is possible should you decide to drive in a docile manner.

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.

Nobody will drive the GT63 4Matic+ and think, ‘Oh, this is OK’, because its breadth of performance is phenomenal.

No matter which mode you're in, from Comfort through to track-tuned Race, the Mercedes-AMG blends forceful pace and commanding control without ever breaking a sweat.

Flex your right foot and the two-tonne coupe bounds into action like a giant on a mission, striding past posted speed limit signs in nanoseconds and way, way faster than the law will stand if diligence isn’t exercised.

And there’s no point relying on seat-of-your-pants sensations, either, because the chassis below embraces the road with an almost zealous devotion. Which is astounding, given how agile the four-wheel steering-enhanced handling is.

The 63’s super power is exactly that – it dulls your sense of speed. One tester admitted to exceeding 150km/h before noticing. An odd confession considering the sonic boombox that is the bi-turbo V8’s howl.

But jailbait performance is not even the 63’s most lingering joy. That would be its steering perfection, that delivers that rare trifecta of keenness, crispness and communication. The wheel feels eager and alive in your hands, even when powering between tight turns, backed up by sensational grip and control. How can a two-tonne GT handle so sharply?

Warm, dry roads were the order of the day, so we can’t tell you how the 4Matic+ permanent AWD system deals with wet or slippery surfaces, but the slick multi-clutch transmission, seamless torque-vectoring tech and sticky tyres more than cope with the 63’s formidable outputs.

So, that's the gushing part out the way, then.

Despite the adaptive dampers, rigid architecture and exquisitely sophisticated suspension, the ride is simply too stiff in Comfort mode, and downright jittery on some of the Tasmanian roads we tested on, for the 63 to be considered a true luxury grand tourer. It just isn't comfortable, luxurious or supple enough.

Plus, grippy as they are, the 21-inch wheels transmit too much road and tyre noise through to the cabin, meaning that the GT isn't as quiet as you'd hope. Add the aforementioned trim squeaks, and the expected cocooned silence isn’t always there.

The upshot is that the 63 possesses more of a sports car character than a luxury GT character. Great news if you're a 911 type buyer and are seeking a high-performance 2+2 alternative, but a disappointment if comfort and refinement are priorities.

Still, it is impossible not to be deeply moved by this Mercedes-AMG.

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.

What’s the GT like to own?

Mercedes-Benz offers a five-year/unlimited km warranty, with five years of roadside assistance. This is average for most mainstream and luxury brands, but superior to most sports-car makers like Porsche and Lamborghini.

Intervals are every 12 months or 20,000km, and while no capped-priced servicing is offered on the GT, pre-paid three-, four- or five-year service plans are available, ranging from $5165, $7700 and $8665 respectively.

Big performance demands big maintenance bills, it seems.

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).