BYD Sealion 5 vs Mercedes-Benz E400

What's the difference?

Cars that don’t always appeal to enthusiast buyers are often seen by manufacturers as a way of not bothering with the dynamics. Good enough is, apparently, good enough. Thankfully, BYD hasn’t taken that path here and the local suspension tweaks have turned what could have been a me-too product into a bit of a dynamic class leader. And even if buyers can’t verbalise the benefits of that, they will still be subliminally enjoying them with every kilometre.

The other stand-out feature is the price-tag which represents an awful lot of car for the money. And, in such a price-sensitive market as this one, that will get the BYD over the line for a lot of families. That it also offers a vastly better driving experience simply makes the value equation – and the purchasing proposition – even stronger.

A convertible that doesn't feel like one when the roof is in place is no easy task to build, but it's one Merc's engineers have pulled off with the E400 4Matic Cabriolet. Effortless power, a tonne of technology and a comfy, leather-wrapped cabin all make Merc's drop-top E-Class a strong proposition.

The interior of the Sealion 5 feels pretty well-made and there are soft-touch surfaces on most of the touch-points. The steering wheel, too, is thick and chunky and nice to hang on to. But there’s a lot going on in terms of different colours, textures and surfaces, and it can all look a bit busy, despite the high-tech boardroom overall flavour. It’s also worth mentioning the trim material is synthetic but does a great job of looking and feeling like real leather.

Externally, there’s not a lot to grab the eye. Sure, it’s not an unpleasant looking vehicle, but neither does it stand out from the mid-size SUV pack. At least BYD decided against those cheap-looking plastic tack-ons on each wheel-arch.

Elegance. That's the word that springs to mind when you first clamp eyes on the E400 Cabriolet. While the Coupe version has a crouched-over sportiness about its exterior design, the convertible is all about big and boat-like proportions, especially with the fabric roof opened.

Like nearly all drop-tops, the E400 looks best with the cabin open to the elements, and the side profile especially paints a picture of well-heeled wafting, with only the AMG alloys and body styling hinting at the performance on offer under the bonnet.

Inside, expect perfectly executed modern luxury, with soft leather seats, touchpoints that melt under the fingers and a sprinkling of woodgrain trim. All of which feel like old-world luxury, nicely juxtaposed by the huge twin-screen display that dominates the dash.

Here’s the other big shock relative to the price-tag of the Sealion 5: This is not a small car. Based on the price, you might have been thinking the vehicle would be a compact SUV. And you’d have been wrong. This is a proper mid-sized SUV with room for five and luggage and an overall length of 4.7 metres and change. And to put that into some kind of perspective, that’s just 30mm shorter than the Sealion 6 which costs about $9000 more at its starting point.

The wheelbase is long, too, and the 2712mm between the axles helps make the interior even more spacious. That means there’s lots of stretching room in the front, but also that a grown adult can comfortably sit in the back seat behind another grown adult at the wheel and still have enough room in every direction. The window sills are commendably low in the rear seat, too, ensuring even littlies can see out.

The biggest problem in the back is that the seat cushion is a bit flat, but, like the front chairs, it’s still pretty plush.

With all five seats in place, the Sealion 5 boasts 463 litres of luggage space and the cargo area is well done with storage pockets at each side, a light and an under-floor tray designed to transport charging cables and a tyre repair kit. Yep, that’s right, there’s no spare tyre of any sort here. No surprise, really.

Fold the rear seat down and you’re suddenly looking at 1410 litres of cargo space and your SUV is now a panel van.

As well as the dual-zone climate control, the Sealion 5 also offers a single USB -C and a USB-A charging port in the front and rear compartments.

The Sealion 5 also offers a V2L (Vehicle to Load) function, meaning it can power camping or on-site work equipment and even act as your home’s battery.

It's a two-door, four-seat convertible, so practicality isn't at the very top of its list of strengths.

That said, life is peachy for upfront riders, both of whom will travel in spacious luxury. There are two cupholders hidden beneath a woodgrain cover underneath the climate controls - also home to a power outlet - as well as a clever double-hinged central storage bin that can be opened by either the passenger or driver, and which opens to reveal two USB points.

There's room in the doors for bottles, too, and the entertainment system can be controlled via a touchpad controller mounted above the traditional click wheel - although, to be honest, using it is harder and more time consuming than simply pretending it doesn't exist.

Climbing into the back (and we mean climb - there are no rear doors) is made easier by the fact you can fold and slide the front seats automatically by pulling a lever mounted near the headrest. Once there, though, you'll find space is a little tighter, and you feel weirdly cocooned, owing to the huge raised tunnel that runs through the middle of the cabin, and the low roof line.

There are two cupholders that live in the space where the middle seat would normally go, and there's a little bottle-holder cubby to the left of both backseat riders. There are air vents back there, too, but no temperature controls.

The front doors are huge and really very heavy, requiring considerable heft to open them.

The boot space is predictably a little limited, with 385 litres on offer. There's also a little flip-down separator, which shows you how much room the roof will need to come down, reducing boot space to 310 litres. Speaking of which, the soft-top can be lowered in just 20 seconds, and at speeds up to 50km/h.

One practicality quirk, though. The front (and only) doors are huge and really very heavy, requiring considerable heft to open them, especially if you're parked on a slight angle. Honestly, I was reduced to kind of pushing them open with my foot at times.

At $157,400, the Cabriolet is the most expensive model in the E400 family, and is roughly $20k more than the sedan and $10k more than the coupe variants.

That money buys you a comprehensively kitted-out ride - as it really should - with the E400 Cabriolet arriving with 20-inch AMG alloys, LED headlights (made up of 84 LEDs) with high-beam assist, proximity unlocking with push-button start, air suspension and Merc's AIRCAP - a lip above the windscreen that's designed to push air up and over the cabin when the roof is down.

Inside, you'll find leather seats, dual-zone climate control and the clever 'AirScarf' system, which pumps hot air onto your neck when the roof is down (and it's cold out). You'll also nab heated front seats, power windows front and back and an automatic belt feeder, which saves you reaching over your shoulder to get to your seatbelt. So exhausting.

On the tech front, expect a killer 590W, 13-speaker Burmester stereo, controlled by the seriously impressive widescreen cockpit; two 12.3-inch screens that spill from about the centre of the dash all the way to the driver's binnacle, and control everything from navigation to Apple CarPlay and Android Auto.

There's a whole bunch of safety stuff, including semi-autonomous technology, but we'll drill down on that under the Safety sub-heading.

Both variants of the Sealion 5 have the same driveline – mostly. They each use a 1.5-litre petrol engine teamed with a single electric motor, both driving the front wheels. Unlike the bigger Sealions, there’s no all-wheel drive version. Power peaks at 156kW and torque at 300Nm.

Why a non-turbocharged engine? BYD tells us the non-turbo engine helps keep cost out of the vehicle and, since the engine really only runs to power the electric motor and charge the batteries, it does so at a relatively constant engine speed, negating the need for a wide spread of petrol power.

The only major difference is that the Essential version has a 12.9kWh battery-pack, while the Premium gets a bigger, 18.3kWh pack for longer range, but precisely the same output and, therefore, performance.

A single-speed transmission is part of the BYD driveline package, also made possible by the fact that the vast majority of the driving of wheels is done by the electric motor.

It's a fabulous engine, this twin-turbocharged V6 - even if it doesn't feel quite so lively in Cabriolet form as it does in the hardtop equivalents.

The 3.0-litre unit produces 245kW/480Nm, sending it to all four wheels via a nine-speed automatic transmission, linked to the standard 4Matic all-wheel drive system.

The Premium’s bigger battery claims to up the official NEDC range from the Essential’s 71km to 100km. BYD reckons with the 52-litre fuel tank brimmed and the car operating at its claimed 1.2 litres per 100km efficiency, the range of either version is just on 1000km. In the real world, that’s likely to be closer to 800km (especially with some highway running thrown in) but it’s still one heck of a solution to range anxiety.

There’s no DC charging function for the Sealion 5, so forget about commercial fast chargers. But on a 3.3kW AC power outlet, the maker claims the Essential can reach full charge in under four hours, while the Premium’s bigger battery will take under six hours to fully charge. A Type 1 charge cable is included.

Mercedes claims 7.4L/100km on the combined cycle (but you can expect to be pushing nine litres in real-world conditions), with emissions pegged at 170g per kilometre of CO2.

The 66-litre tank will only accepts 95RON fuel.

You don’t have to drive very far to realise that the local input into the Sealion 5’s suspension and steering have been worth the effort. BYD Australia has a local engineering team on call these days, and it shows here.

Actually, the steering is not the highlight; it has some weight but not a whole lot of feel, or, indeed, feedback for the driver. The ride and handling combination is what stars. Obviously well-damped, the suspension allows for a ride that is both complaint and quiet, without causing the car to wallow around like some jacked-up designs can with their higher centre of gravity.

In fact, the BYD is athletic to the point where keener drivers will find it an entertaining drive; hardly something that can be said for the majority of medium SUVs.

Performance is strong without being overwhelming and even though the Sealion 5 has that signature electric-drive feeling of effortlessness, the accelerator pedal has been calibrated to avoid the neck-snapping surge of grunt off the line. As such, it emerges with a fairly flat acceleration curve, and no hint that the petrol motor is cutting in or out.

Until, that is, you bury the throttle all the way at which point the petrol engine takes a few second to join in. And when it does, it’s pretty vocal – shrill, almost – as it catches up with the rest of the car and starts directly driving the wheels. To be fair, though, this is not going to be a common occurrence in everyday life thanks to the flexibility of the petrol-electric system for 99 per cent of circumstances.

On the move, the cabin is perhaps most notable for its soft, plush seats that are a nice change from the church pews of some manufacturers. And although the driving position is about right, taller drivers might prefer a steering column that extends out another few millimetres.

The driver display screen is another source of annoyance. It’s pretty small and contains lots and lots of information, to the point where the typeface is too small to be read on the run by anybody who relies on reading glasses.

Sure, the E400 Cabriolet can drive itself, but we’re equally pleased to note that it’s still a lot more fun handling the steering duties yourself.

And that is mostly due to that fabulous engine; quiet and effortless at city speeds, rorty and enthusiastic at pace, and genuinely angry with the drive setting switched to their most hardcore Sport+ mode.

We’ve already spent time in the sedan version, and while this Cabriolet is heavier (1935kg vs 1820kg) and slightly slower to 100km/h (5.5sec vs 5.2sec) it doesn’t immediately feel it behind the wheel, with a similar and satisfying lurch into the future when you plant your foot.

But hard charging is not what this car is about, and the E 400 is at its peachy best when rolling about the city or the ‘burbs with the top down, and the warm summer air washing through the cabin.

In its normal drive settings, the steering is light but engaged, and the ride on offer from the standard air suspension is outstanding, cosseting the cabin from all but the very worst road imperfections, while the torque from the V6 serves up effortless, unobtrusive acceleration.

With the roof up, Merc’s designers have done a stellar job of hiding the fact this thing is a convertible at all. It’s a solid-feeling cabin with the fabric roof fastened, and the cabin is quiet and free from wind noise.

There are few cars on the road as overloaded with safety technology as the E400 Cabriolet.

The standard stuff is all there, of course. There's a 360-degree parking camera, as well as nine airbags (dual front, dual pelvic/thorax for front-seat passengers, dual sidebags for rear passengers, dual head bags in the doors and a knee airbag for the driver), rollover protection and tyre-pressure monitoring, as well as braking and traction aids.

But the E400 adds some really clever technology, including Merc's Driving Assistance Package Plus, which adds active lane keeping, blind-spot assist, cross-traffic alert and evasive steering assist.

It's this suite of systems that allows the E400 to navigate freeways autonomously, including changing lanes on demand. At the moment, the system will warn you to keep your hands on the wheel every so often, but you can sense a time when that will no longer be required. And that time is soon.

The E-Class range scored the maximum five-star ANCAP safety rating when crash tested in 2016.

Like other BYDs, the Sealion 5 comes with a six-year/150,000km warranty. Some of the competition have unlimited kilometre warranties, but to be honest, 150,000km in six years is going to be beyond the need and aspirations of most owners.

The EV battery is covered by an eight-year/160,000km warranty, and let’s not forget, BYD was a battery manufacturer before it started making whole cars. Certainly, the company is very bullish about the quality and safety of its 'Blade' battery technology, claiming it easily passes the technically-daunting 'nail-puncture' test.

BYD plans to have capped-price servicing for the Sealion 5, but no pricing announcements have been made yet.

Servicing also falls into line with other BYD models, so that means 12 months or 20,000km intervals.

Expect the usual three-year, unlimited-kilometre warranty, with service intervals pegged at 12 months or 25,000km. Mercedes' capped-price servicing scheme limits maintenance costs to $2280 for the first three years of ownership.