Leapmotor B10 vs Mercedes-Benz SL63

What's the difference?

I’ll be a shame if the B10 doesn’t sell well, because it doesn’t suffer from many of the downfalls of its compatriots and its price is extremely competitive for what you get.

As a comfortable smallish SUV, it meets par, and it’s on the better side of tech when it comes to cars from China, and it doesn’t have any major on-road red flags.

You really wouldn’t be disappointed with this having paid $40K, just skip the base model and go for the Design.

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

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.

Right after we praise the B10 for its value, we need to talk about its looks. A slight drop in tone as the second Leapmotor to land in Australia looks an awful lot like the first, and it’s relatively bland.

It’s not ugly, but it’s not particularly inspiring and there’s not much character to this little electric SUV.

It’s got a very upright silhouette at the front with a slightly sloping roofline at the rear, so the overall shape is appealing, but the lack of distinct features makes the B10 an anonymous commuter for now, especially with its similarities to the C10.

You can tell them apart by the C10’s slightly larger size if they’re near each other, or the B10’s more in-line headlight bar, where the C10’s have a ‘droop’ at the sides.

The large section of black at the lower half of the front is also unappealing, though darker colours like the optional 'Starry Night Blue' or 'Dawn Purple' (both $990) blend into it better than standard 'Light White'.

To its credit, at least the B10 doesn’t fall victim to the design crutch of adding trim and plastic for no reason.

In terms of the specifics, the B10 is 4515mm long, 1885mm wide and 1665mm tall with a 2735mm wheelbase, making it quite the large small SUV.

Inside, the cabin looks and feels roomy thanks to the test car’s light interior, decent windows and the light from the sunroof, as well as the fact the EV powertrains are compact and generally don’t interfere with cabin space.

Materials aren’t all scratchy hard plastic, though it is dotted around, and the general look of the B10 inside feels more premium than its price would have you thinking, despite the simplicity of the layout and design.

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.

Getting into the B10 requires a minor annoyance - unlocking and locking the car requires a keycard to be tapped on the drivers’ side mirror like you're scanning to access your floor in a hotel elevator.

There’s an app that adds a fair bit of functionality, but having to whip your phone out ahead of jumping in the car is also irritating.

Once you’re in, though, the space inside the B10 is well laid-out, even if much of its functionality is crammed into the big central touchscreen - it’s always ‘points off’ for a lack of physical buttons in this section of a review.

Once you’re used to it and have sorted out your personal settings on the multimedia software, it becomes more natural and less distracting, though Apple CarPlay and Android Auto would occasionally lag in the car on test.

The good news is they now exist for the brand in the B10, with the Leapmotor C10 still lacking the vital in-car mirroring tech.

The ergonomics and interior space work well, generally, with comfortable pews and good vision, plus decent spaces to keep things out of the way. The phone charger being in a very visible and accessible position might tempt some naughty screen-keen drivers, and being in the sun without a vent for cooling while charging means your phone will get proper hot.

The second row is extremely spacious, belying the fact this car is classified as a small SUV. Oodles of legroom and enough headroom for a tall adult means the B10 outguns rivals in terms of good options for parents (note the B10’s extremely strong 95 per cent child safety score from ANCAP, too) or anyone who needs to cart humans around regularly.

Behind the second row is a 490L boot, which becomes 1475L when the second row is folded down.

There’s space under the floor for cables and messy bits, but unfortunately no spare wheel, just a tyre repair kit, so more points off for that.

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.

Priced at $373,370, before on-road costs, the new SL63 4Matic+ will be battling top-shelf performance soft tops including (in ascending dollar order) BMW’s M850i xDrive Convertible ($307,100), the Porsche 911 Carrera GTS Cabriolet ($386,900) and even exotics like the Lamborghini Huracan RWD Evo Spyder ($422,606). 

Value for money is a relative concept in this part of the market, although equipment highlights include a head-up display (with augmented reality nav), 11-speaker, 650-watt Burmester surround sound audio, ambient lighting (choice of 64 colours), hectares of Nappa leather trim, dual-zone climate control, an 11.9-inch central multimedia screen (running Merc’s latest ‘MBUX’ software), 12.3-inch configurable digital instrument display and 21-inch forged alloy rims.

There’s also the ‘Digital Light System’ built around three high-power LEDs in each headlight, refracted and directed through 1.3 million ‘micro-mirrors’ to create a combined resolution of 2.6 million pixels.

The ‘Neck Scarf’ function is added to the top of the front seats to keep your neck and the back of your head warm as the temperature drops, the heated, ventilated and massaging front seats feature eight-way electric adjustment and three memories, there’s a heated steering wheel, Android Auto and Apple CarPlay connectivity, wireless device charging and more.

Worth noting the big 21-inch rims in a ‘10-twin-spoke’ design are standard issue with an alternate ‘multi-spoke’ pattern available as a no-cost option. 

But if all that’s not enough you can opt for ‘AMG Performance seats’ ($2490) which grip you even more securely but delete the massage function.

Or there’s the ‘AMG Night Package’ ($6990) which adds wheels in matt black (with “high-sheen finish rim flange”), darkened head- and tail-lights, an aero package, black badging, black radiator fins and interior trim elements in black chrome.

Then you can go the whole hog with the ‘AMG Carbon Fibre Package’ ($11,990) which brings the wheels in matt black, exterior carbon elements, carbon mirrors, carbon interior trim and a steering wheel in a combination carbon-fibre and Dinamica (synthetic microsuede).

There’s only one powertrain option for the Leapmotor B10, a single, rear-mounted electric motor that produces 160kW and 240Nm, which makes the electric SUV good for a claimed 0-100km/h time of 8.0 seconds in both variants.

Top speed is a claimed 170km/h, also regardless of the variant.

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.

Leapmotor claims the B10 will, from its LFP battery of either 56.2kWh for the Style or 67.1kWh for the Design LR, draw 17.2kWh/100km or 17.3kWh/100km, respectively under WLTP testing.

The result is the Style offering up a 361km WLTP-tested driving range, and the Design LR a more useful 434km.

While we were unable to properly confirm this claim on the launch, the trip computer after a mix of highway driving and more spirited back-road testing displayed a figure of 13.5kWh/100km, while the previous 1447km of driving had reportedly measured in at 14.7kWh.

Charging from 30 to 80 per cent takes approximately 20 minutes regardless of spec and battery size. The smaller battery can be charged via DC fast-charging at a maximum 140kW, and the larger at 168kW. Both max out at 11kW under AC charging.

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.

The Leapmotor B10 was developed with testing at Stellantis’ European proving ground in Italy. This is because despite Leapmotor being its own brand within China, its international operations are a joint-venture between itself and Stellantis.

There are some on-paper shreds of evidence for this, a rear-wheel drive layout and a claimed 50/50 weight distribution help, but get the B10 on the road and it’s clear this isn’t a car that’s relying entirely on price, a long list of features and some showroom shine to sell.

After the initial familiarisation that comes with many new electric cars, particularly from China, the Leapmotor B10 becomes easy to settle into a rhythm with, especially if you turn off some of its more intrusive ADAS features like lane-keep, driver monitoring and speed limit warning. The latter can sometimes get a limit wrong, and though the B10’s chimes aren’t audibly overbearing, they are persistent.

While the B10 doesn’t excel in any areas on the road, it doesn’t fall down significantly in any either.

Its suspension soaks up bumps relatively well, and despite some vibrations on rougher roads the B10 is pretty comfortable. The tyres it rides on as standard, however, are rather noisy, so if there’s an opportunity to swap out the Linglong defaults to something better, we’d advise it.

The tyres also squeal rather quickly when cornering, not necessarily because the B10 is about to let go, but just because the weight of the car appears to be pushing on the front outside tyre in cornering.

The B10 holds up better than\ a family car really needs to in dynamic driving, but we wouldn’t be doing mountain runs or track days in one. 

There’s a little body roll in corners, but not nearly as much as has been in other models riding on the apparently soft suspension preferred in China.

The steering, braking and acceleration all have a mild vagueness to them, but once you’re honed in they’re all predictable. The steering can be adjusted for weight, and its lightest setting is too light, while the acceleration feels lethargic in its lowest setting and too aggressive in its highest.

There’s not a lot of regenerative braking strength, but it’s enough to help regulate speed once you’re used to how mildly it comes in - again, depending on your preferences and settings.

The good news here is that the B10 is easy to drive, and only very serious road bumps on fast corners unsettled it on test - the kind you’d expect to upset any car.

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.  

No independent ANCAP safety assessment at this stage but the SL63 is fitted with the ‘Driving Assistance Package Plus’ which includes a heap of active (crash-avoidance) tech including AEB (with pedestrian detection), active cruise control, lane keeping assist, lane change assist, traffic sign assist, ‘Active Traffic-assist’ and ‘Active Steering Assist’. 

There’s also tyre pressure monitoring and the ‘Active Parking Assist with Parktronic’ self-parking system supported by a 360-degree camera view and multiple sensors. 

If a crash is unavoidable the airbag count runs to eight, including side bags for rear occupants. There are ISOFIX anchor points for child seats or baby capsules in the two rear and front passenger seat positions. And an active bonnet is designed to reduce injuries in the case of a pedestrian impact.

The B10’s post-purchase prospects are generally solid, though Leapmotor’s six-year, 160,000km warranty is an area where it falls short of rivals which are offering longer, unlimited kilometre warranties.

The battery is covered for eight years or 180,000km, whichever comes first, which is pretty par for an EV.

Servicing is capped-price for the first eight years, with each service costing $370 on average. The eight-year span makes it pretty appealing, per 12-month interval or every 20,000km.

There are currently 20 dealers across the country, though more are coming, while Leapmotor also offers eight years of roadside service.

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.