Mercedes R-Class

No other manufacturer has more niche models than Mercedes. Time will tell if there really is a gap in the UK market for a grand tourer such as the R-Class, but it should attract customers looking for a big cabin and a premium badge who don't want a large off-roader.

Whether it's by train or plane, there's nothing like travelling first class. With enormous seats and uncompromised luxury, Mercedes wants its new R-Class to be the automotive equivalent. But will buyers be prepared to pay for an upgrade?

On sale in the UK next month, the premium estate will be available in standard and long-wheelbase forms. Both offer three rows of two seats, along with a choice of two petrol engines or a diesel unit. Surprisingly, 70 per cent of sales in Britain are expected to go tothe long-wheelbase version, so we drove the R320L CDI.

Sharing its underpinnings with the M-Class, the biggest all-wheel-drive R-Class is huge - 369mm longer than its off-road sibling, with a 3,215mm wheelbase. Both rows of passenger seats provide plenty of leg and shoulder room, while even the rearmost pair offer acceptable headroom. Easy access to the back is made possible by middle chairs that slide forward, and large rear doors - although the size of the latter means there's not room to open them fully in car parks.

With a raised driving position and huge dimensions, the R-Class handles like an SUV, but a lower centre of gravity means it doesn't suffer the ponderous changes of direction that afflict many off-roaders. There's little steering feel, but despite its size the R320 is stable when cornering. The diesel powerplant, proven in other models, is strong and refined.

Air-suspension is an option, but our test model sat on conventional springs and offered decent comfort. If you've got a long journey to make, the R-Class is about as relaxing as any car can be.