Mercedes-AMG S63 vs Tesla Model X

What's the difference?

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.

After nearly 700km of testing with both cars, it’s fair to say that the Tesla is indeed a capable tow vehicle, provided you keep the distances relatively short and plan around charge station locations.

Overall average - Penrith to Bathurst to Penrith

Fuel and energy consumption will always depend on the driving conditions, which is why we chose different routes for each leg of our testing.

Averaged across the two legs, towing the caravan with the Model X used 101 per cent more energy than without, or halved its driving range, which sounds a bit scary.

The LandCruiser by comparison added 63 per cent on average, which is still a big difference, but matters less in the real world when its big fuel tanks would still give you about 760km of driving range, which can be refilled quickly at any diesel-stocked servo.

So you could do a weekend trip with the caravan from Penrith with one supercharge in Bathurst, but it would’ve been highly unlikely to manage the extra 55km if you were leaving from Sydney CBD.

The bottom line is that there’s plenty of things - like smaller camper trailers - lighter than our caravan that will help the Tesla to do the towing job better right now.

Compared to the ‘Cruiser, the Tesla is a lesson in the benefits of a lower centre of gravity and road-focused handling.

As always, bigger batteries and more recharge points will go a long way to rectifying the Tesla’s towing shortcomings, and I'm sure we'll get there eventually.

But no matter what, its acceleration performance under load is simply excellent.

Thanks to our friends at Avida for making this test possible with the use of the 17-foot Avida Wave Tourer Electric Pop-Top single-axle caravan. They can also be reached on 1300 428 432.

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.

Energy consumption is just one element of a tow vehicle though, with stability, braking and acceleration performance being the most important details.

The big ‘Cruiser is always a safe bet for towing heavy loads, but it's fair to say its off-road ability, tall body and short wheelbase mean it could be better on the road, and the Tesla goes some way to proving that.

With all those batteries mounted nice and low, the Tesla is significantly more stable with 1.7 tonnes on the back than the LandCruiser, in all conditions. It’s also helped by that longer wheelbase.

The Tesla’s airbag suspension is another surprise advantage, and while it can be a bit choppy around town over minor bumps, bigger bumps on the highway are soaked up really nicely and it all settles quicker than with the LandCruiser - even with the caravan on the back.

Tesla is famous for instant acceleration at any speed, and this effect remains when towing. The LandCruiser’s twin-turbo V8 (with max torque available from 1600-2600rpm) has long been a benchmark for tow vehicles, but the Model X makes it feel sluggish by comparison.

You know how caravan vehicles are usually the slow ones up hills? This time, we were the ones doing the overtaking, even up the steep bends heading out of Lithgow. To overtake, it just takes the slightest flex of your right foot.

Clearly there’s a big caveat though when it comes to how much energy it’s consuming while you’re enjoying that performance, and it’s deceptive because it doesn’t make any more noise like a conventional engine when you’re pushing it. 

You’d also think the weight of the van would overcome the engine-braking effect of the regenerative brakes, but they are still very effective at conserving your brakes downhill and preventing the car from running away from you, and no doubt giving the batteries a bigger boost at the same time.

On that note, the LandCruiser’s cruise control also does a great job of witholding speed on downhill runs, proactively dropping gears to engine brake enough to keep the Avida Wave in check.