Stuttgart's recipe is exactly the same as Munich's: design a four-door coupe body with much less interior space, plonk it on the chassis of a wagon-style SUV, then charge extra for something that's less practical and awkwardly proportioned.

As BMW based the X6 on its X5 wagon, so the rival Mercedes-Benz GLE Coupe is based on the GLE (the vehicle formerly known as M-Class).

Benz believes its strategy will work as well as it did for BMW, especially in the world's single largest car market. "We think China will be the biggest market for the vehicle," says vice-president in charge of SUVs and sports cars Wolf-Dieter Kurz.

Three GLE Coupe variants will sell in Australia from September, costing thousands more than their nearest GLE wagon equivalents. The least costly will be the $121,900 350d, with a 190kW 3.0-litre V6 turbodiesel and nine-speed auto.

Mercedes-Benz Australia expects the more expensive petrol models will prove more popular. The $141,900 450 AMG has a 270kW 3.0-litre twin-turbo V6 and nine-speed automatic transmission, while the $198,900 63 S has a 430kW 5.5-litre twin-turbo V8 and seven-speed auto. All GLE Coupes come with Mercedes-Benz's 4Matic all-wheel-drive.

No matter which version you choose, the interior of the GLE Coupe is lavishly kitted out. Nappa leather is standard in all, as well as AMG Line sports front seats, 14-speaker Harman Kardon audio and Mercedes Comand navigation setup.

For the pair riding in the front seats, the ambience is truly luxurious. The rear seat is decently roomy, despite the swooping roofline.

However, the compromises involved in creating an SUV that's also a four-door coupe are obvious.

Mercedes claims the GLE Coupe's cargo compartment, 1720L seats down, is the largest of any coupe (a world's-tallest-dwarf kind of boast).

Fact is that, rear seats up, the volume is 40L-50L shy of the donor wagon, and its loading lip is inconveniently high.

Drive the GLE Coupe and other shortcomings are apparent.

From the driver's seat, its front corners are invisible. At a fraction over two metres wide, it's a very bulky vehicle and the inability to envisage its extremities makes driving it more daunting than it should be. Rearward vision isn't great either.

CarsGuide focused on the 450 AMG and the 63 S at the international launch in southern Germany and Austria.

Mercedes-Benz engineers have tried very hard to endow sporty handling — the steering is more direct than in the GLE wagon, for example. For Australia, air suspension with adaptive damping and very large wheels will be standard spec.

The GLE is agile for something so high and heavy but even Benz's nothing-but-the-best development budgets can't rewrite the laws of physics. The 2.2 tonne-plus kerb weight of the 450 AMG blunts the performance of its excellent engine, which makes it a calmer car to drive than the feral-fast and even porkier 63 S.

With its big V8 bellowing, the top version of the GLE Coupe can be hustled along a winding road at a very speedy clip. But it's no quicker, according to the maker's own figures, than the little A45 stablemate.

Just like that hot hatchback, and despite its massive tyres on 22-inch wheels, the 63 S will push wide on corners as its front rubber loses grip.