BYD Sealion 8 vs Mercedes-AMG S63

What's the difference?

There’s no denying the value the BYD Sealion 8 Premium offers as it packs a lot in for the price. Its efficiency and inoffensive looks add up to a good package and reflect what it does well. That said, the underwhelming driving experience and clunky media system are noticeable. Whether they're deal breakers is up to you.

Both of these vast vehicles are phenomenally comfortable - this is the kind of car that Mercedes does so well, and has done for decades. The S Class is rarely a disappointment but it's difficult to believe that such a big, heavy GT car can also dance the way the S63 does.

The S560 is far more weighted to being a GT - supremely comfortable with that active suspension, a growly, refined V8 and a cabin full of gadgets and comfort. The S63 is altogether more aggressive, to look at and to drive. Lopping the roof off both of them adds weight but, like any cruiser, also puts you out in the sun, the breeze and into your surroundings. Plus, in the case of the S63, you get more exhaust noise.

They're two very different cars and not just because of the engine. After all these years admiring it from afar, the S63 has delivered on my teenage expectations - fast, smooth and utterly mad.

The Sealion 8 is a big unit, and its design leans more towards soft and rounded than sharp. There’s a sense of restraint with its pillowy panels, smooth curves and flush door handles all contributing to a clean, almost clinical look.

The 21-inch wheels add a bit of presence, as does the full-width LED light bar with its braided design. But overall, it doesn’t try too hard to stand out. It’s inoffensive - clean and easy on the eye, but it stops short of having any sense of identity.

Inside, the cabin carries that same restrained approach. There’s black leather upholstery, some interesting geometric detailing through the panels and speaker grilles and a generous use of soft-touch materials throughout.

The large displays and panoramic sunroof help lift the space, giving it a premium feel, but more importantly, it’s just a comfortable, easy place to spend time. Which, for a family SUV, arguably matters more than anything else.

The S Class Coupe is obviously related to the sedan but manages a svelte appearance. Slimmer hipped and with a more Coke-bottle shape, the Coupe - if you squint a bit - has a bit of the classic old pagoda about it. Obviously you can't do pillars that slim anymore, but the glass roof takes away some of the visual weight inside and out. 

The cabriolet's roof is nicely integrated and looks good when it's  up, which isn't always the case.

They all look long, though. It's obvious to see why the cars all run on 20-inch wheels - anything smaller would look hilarious.

The cabin is a fairly sensible re-imagining of the E-Class. The big twin-screen layout of the dash and multimedia system seems a bit more at home here. The chintzy Burmester speakers in the doors let down an otherwise classy cabin, which steers clear of otiose vulgarity in looks and materials.

Up front, storage and general usability are well thought out. There’s a handy shelf tucked underneath the centre console with two USB-C ports, while a tray above houses the fast wireless charging pad. You also get a sunglasses holder, two cupholders and decent-sized bottle holders in the doors, so it’s easy to keep things organised.

Seat comfort is a highlight, and the overall layout is clean and easy to live with, but the same can’t be said for the multimedia system. While the graphics are sharp and the touchscreen is responsive, functionality isn’t always its strong suit. Wireless Apple CarPlay and Android Auto are included, but CarPlay required reconnecting on every drive during testing and the digital radio and phone calls experienced noticeable signal dropouts. It’s the kind of friction that chips away at the day-to-day experience and starts to feel out of step with how polished the rest of the cabin is.

There’s also a heavy reliance on the screen for core functions. Climate control is integrated, which is fairly standard, but so too are things like headlight controls. It might suit those who are used to navigating everything through a screen, but needing to dig through menus to adjust something like auto high beam on the move feels like a step too far. Bring back buttons.

The second row is where the Sealion 8 really leans into its family-friendly brief. Space is generous, with enough width to comfortably accommodate three adults and the flat floor helps here too. There are three top tether points and two ISOFIX mounts, while charging is covered by a USB-A and USB-C port.

Amenities are a standout. The outboard seats mirror the front with heating, ventilation and massage functions, which quickly become a favourite, alongside dedicated climate controls, roof-mounted air vents and multiple cupholders. A set of sunshades would round things out nicely, but it’s otherwise a very accommodating space.

Access to the third row is less impressive. The manual slide and tilt mechanism feels a little heavy and fiddly to operate and the space itself is best reserved for kids. In practice, that means younger passengers will likely take the path of least resistance, as mine did and simply climb over the second row instead.

Amenities are fairly basic, with directional air vents and cupholders, but there’s no charging provision back there. You do, however, get two top tether points and ISOFIX mounts, which will be a plus for larger families.

Around the back, the boot is a practical, usable space with a wide opening and flat loading floor. With all three rows in place, there’s 270L on offer, which is enough for a few school bags or a grocery run, expanding to 960L with the third row folded. There’s no spare tyre, just a repair kit, which may be a consideration for regional drivers. A 12-volt socket and powered tailgate round things out in this grade.

Well look, if you end up in the back of the S Coupe, it's not a riot of space. Obviously it has back seats (the SL doesn't even squeeze a jump seat into its considerable length) but they're for occasional, if luxurious, use.

The boot is a reasonably decent 400 litres, obviously the cabriolet loses a few litres with the roof folded. Front and rear passengers will both enjoy a pair of cupholders and the whopping long doors will each hold a bottle.

One thing hasn't changed in nearly 20 years - the S isn't cheap. Available in coupe and cabriolet, the S560 starts at $314,900 for the former and $336,900 for the latter. Step up to the S63 pair and you'll pay from $370,500 for the coupe and $399,900 for the cab. If you're super keen for something spectacular, the twin-turbo V12-powered S65 is available for between $508,900 and $520,500, and features Swarovski crystals in the headlights, for some reason.

As you can imagine, there's quite a bit to cover, so for both cars I'll stick to the edited highlights. The S560s roll on 20-inch alloys, has a 590-watt 13 speaker sound system, digital TV, auto parking, active cruise control, panoramic glass roof, Nappa leather, active seats and power-closing doors.

It also comes standard with a heating pack that not only heats the seats but the steering wheel and centre console. In the cabriolet you also get the 'Airscarf' neck heater.

Both cars also feature's Mercedes' Magic Body Control with curve function. More of that wacky feature later.

The S63 AMG is a step up in power, price and spec. One notable change from the S560 is the loss of 'Magic Body Control', which is replaced with mere air suspension. The 20-inch alloys are 10-spoke forged units, the brakes higher performance composites with red calipers, while an AMG sports exhaust brings the noise.

Naturally, both are swathed in high-quality leather and feature dual-zone climate control, heated and cooled electric seats that adjust in every direction, deep carpets, keyless entry and start, fully digital dashboards and just about every gadget to which you can point your imagination.

Entertainment and sat nav are via Mercedes' 'Comand' system, which is displayed on a massive 12.3-inch slab of glass at the top of the dashboard. The 13-speaker Burmester-branded system is predictably impressive and with Apple CarPlay and Android Auto, you only have to use the basic software for the radio or various car controls.

The BYD Sealion 8 Premium is all-wheel drive and pairs a 1.5-litre, four-cylinder, turbo-petrol engine with two electric motors, one on each axle. Combined outputs sit at a hefty 359kW and 675Nm, which comfortably out-muscles its key rivals.

Those figures do drop back to a more modest 110kW and 220Nm when running on the petrol engine alone.

Performance is strong for a large family SUV, with a claimed 0-100km/h sprint time of 4.9 seconds. You can toggle between pure EV and hybrid modes depending on the drive, which adds a layer of flexibility that suits short daily trips and longer highway runs.

All four coupes and cabriolets ship with Daimler's formidable 4.0-litre twin-turbo V8. The S560 scores 345kW/700Nm to drive the rear wheels through Benz's own nine-speed automatic. With all of that available, the S560 will crack the ton in 4.6 seconds and make a wonderful racket on the way.

Moving on to the S63, the same engine delivers a massive 450kW/900Nm. The run from 0-100km/h is dispatched in just 3.5 seconds and if I thought the S560 made a good noise, the S63 with its standard sports exhaust makes a better one. Again, Mercedes' nine-speeder is along for the ride.

Charging is handled via a Type 2 CCS port, with support for up to 11kW on AC and up to 74kW on a DC fast charger. BYD claims a 30 to 80 per cent recharge can be done in as little as 20 minutes under ideal conditions.

The 35.6kWh lithium iron phosphate (LFP) battery is a standout, delivering a claimed electric-only driving range of 152km on the NEDC cycle. That figure is on the optimistic side compared to WLTP testing, but even with that in mind, it remains an impressive number for a plug-in hybrid of this size.

With a full battery, the combined fuel consumption is rated at just 1.0L/100km, translating to a theoretical driving range of over 1000km. Real-world results will vary depending on how often you’re able to charge and the type of driving you’re doing, but after a week that included a fair stretch of highway driving, my trip computer was showing 6.3L/100km. Overall, it’s a solid result, particularly for something with this level of performance.

The lower-powered 560 drinks 98RON at the rate of 8.5L/100km for the coupe and 9.9L/100km for the heavier cabriolet.

The S63 ups the ante with 9.9L/100km for the coupe and an identical 9.9L/100km for the cab.

Our launch program contained some...er...spirited driving, which would explain the mid to high-teens fuel figures.

On-road performance is where things become a bit of a mixed bag. There’s no denying the Sealion 8 Premium is quick and it leans more heavily into its EV character than many large plug-in hybrids. It’s quiet in hybrid mode and responsive off the mark, which makes it easy to keep pace in traffic and overtake when needed. For something of its size, it also does a good job of masking its weight on the move.

Regenerative braking is offered in two levels, but even the stronger setting feels fairly mild. The upside is smoother low-speed driving, with none of the abruptness you sometimes get in hybrids, and it does still recover a decent amount of energy, particularly on longer descents.

Where it falls short is in its overall dynamics. The steering and suspension are tuned for comfort, which results in a soft, slightly floaty feel on the road. It’s not unpleasant and around town it actually suits the car’s brief, but there’s a noticeable lack of feedback and control if you’re expecting something more composed.

Visibility and driver positioning also take some getting used to. The forward view is decent, but the pillars are quite thick and it can be difficult to find a driving position that doesn’t feel a little enclosed.

Judging the edges of the car isn’t always intuitive, and while the 360-degree camera is clear, its perspective can feel slightly off. Objects tend to appear much farther away than they are, which isn’t the most reassuring combination when you’re trying to manoeuvre in tighter spaces.

Let's start with the S560. That smooth V8 rumble is all you'll ever hear if you just slot into drive and go for a leisurely spin. The nine-speed automatic continues to be a revelation to me - in the GLC63 it's good and here, once again, it's excellent, finding the right gear for the occasion and riding the fat torque curve. Other nine-speed autos are not very good at all.

The test route for the S560 played to the strengths of the car. It had some lovely winding roads, which brought the trick suspension into focus - the Magic Body Control with curve function is hilarious. While the active suspension works hard at all times to ensure the ride is smooth and drama free, the Curve mode (no, really) actually leans the car into corners.

Those of you who remember the video game Wipeout 2097 will be big fans of Curve mode. As you approach a corner, you turn the wheel and then the car leans into the bend. This isn't active damping reading the road, it's the outside suspension lifting the car and the inside lowering it, so the car feels like it's gliding, like a hovercar. It's wild but oddly calming. Mercedes reckons it's great for those who get car sick. As I didn't have my wife on hand to test this theory - she chucks at the first sign of a corner - I couldn't verify this claim. That will have to wait.

The S63 AMG is a completely different proposition. The air suspension is more than up to the job of helping smother the effects of the car's considerable weight, meaning that no matter what you're up to, the car feels reasonably light on its feet. It never feels small, though, commanding the respect of the driver and plenty of space from other road users.

And boy, do you need some space if you kick the S63 into Sport mode. In true AMG style, the electronic reins relax and the big luxury coupe cheerfully kicks off. The tail will wriggle under an unsympathetic right foot, that signature V8 roar, crackle and hiss filling your ears. The S63 is always the harder-feeling car, but it delivers with a more sporting drive than the S560.

Being the generous soul I am, I volunteered to return the S63 to its home for the evening rather than consign it to the back of a truck. On the back roads I took to reach the highway, it was rock solid - fast, predictable and a lot of fun. Once I found the boring straight bits, it turned into a supremely comfortable cruiser, ticking along in ninth at the legal limit (and being Melbourne, it was very much the legal limit), dispatching overtaking with barely a flex of a toe. 

The active cruise took the stress of keeping away from the State Revenue Office's clutches while being quiet and utterly pleasant.

The S-Class coupe comes loaded with eight airbags, ABS, stability and traction controls, forward and reverse AEB with pedestrian detection, reversing camera, crosswind assist (I know, right?), traffic-sign recognition and reverse cross traffic alert.

The S-Class Coupe does not have an ANCAP or EuroNCAP rating.

BYD offers the Sealion 8 with a six-year/150,000km warranty and an eight-year or up to 160,000km battery warranty. Both terms are competitive for its class.

Service is recommended every 12 months/20,000km with each workshop visit averaging a solid $596 for the first five years (year four is $1360). Accessing a BYD service centre is fairly easy as there are around 70 centres nationwide now.

BYD recommends premium unleaded petrol (95RON) to be used for the Sealion 8.

Mercedes offers a three-year/unlimited-kilometre warranty with roadside assist for the duration.

The company also offers both service plans (where you pay up-front as part of the vehicle purchase) and capped-price servicing on the coupes. Servicing over three years is in the order $2500.