SECTOR Saloon/Coupe  PRICE £63,900  FUEL 49.6 mpg  CO2 148 g/km

When it comes to fitting new cars into niches, it has often been the case that you take a couple of doors away, or lop a roof off. But in recent years, there’s been a switch back in the other direction.

Thanks to Mercedes-Benz and its wonderful CLS, manufacturers have realised there’s quite a market out there for slinky-looking cars which still have a decent amout of practicality.

Hence the new BMW 6 Series Gran Coupe, which manages to retain much of the stylish, slashed lines of the Coupe version, but adds in a couple of rear doors for good measure. The result is a head turning coupe-saloon with considerable space and a magnificent engine in the form of the twin turbo 640d.

This 313bhp six-cylinder engine offers CO2 emissions of only 148g/km and combined fuel economy of 49.6, as well as truly remarkable performance (0-62mph in just over five seconds), all wrapped up in a luxurious package that should suit any executive perfectly.

It’s not cheap though, coming in at more than £60,000, which is some way over the CLS 350 diesel, which is our current luxury car of the year, and the new bi-turbo Audi A7, a car more than £10,000 cheaper.

But the 640d Gran Coupe is more refined, bigger and handles impressively too when compared to its rivals. In fact, it is a perfect car for a high mileage driver who needs to be kept in luxury. The addition of a Comfort Plus mode, which makes the car all soft and squidgy, and ECO-PRO to maximise fuel efficiency means the Gran Coupe has all the bases covered.

The question for any executive would be whether the big, elegant BMW is worth the extra investment over the other two, although the quality of the car is not in doubt. I'd say it is – it really is a complete machine, and proves niche cars need not be a compromise.