BMW 6 Series Gran Turismo review

It's remarkably refined and isolating. A brilliant thing for passengers, and for drivers too, on a long long haul or a dreary commute. But it's not going to light up a smile behind the wheel on an interesting road. Even though it'll tackle difficult and twisty sections at big speed, it's just not that engaging.

The test car had the full Christmas tree. Powered by the top-end 40i engine which comes with all-wheel drive, it added a £4,300 package of four-wheel steering, adaptive damping, air suspension at each end, and 'Executive Drive' adaptive anti-roll.

The combination is extremely capable. It steers progressively and has enormous traction and composure. The adaptive suspension's control of body movements is disciplined and yet graceful. It feels analogue not digital; you can't work out what element of the system is responsible for what characteristic, but you know they work fluently together.

Some active chassis get themselves so stiff during hard cornering that when a mid-bend bump arrives, they strike it with a crash. Not this one; it always seems to have something in reserve.

So you're quick and confident and secure. But the steering has little feedback and the throttle has scant influence on the feel of the car through a bend, either. Just when you want to have a bit of fun with the GT, it turns its face against you and goes coy and aloof.

Maybe the 630i, with a smaller engine and two-wheel drive and a lot less weight, would ease the issue. But as we write this we haven't had the taste of one. The 630i's 6.3sec 0-62mph time looks quick enough.

When you give the 640i's six-cylinder turbo engine a pasting, it does more to warm your heart. Its sound is muted going gently but the noise is deliciously charismatic as it revs and shoves you in the back. BMW's published 0-62mph time of 5.3sec is entirely believable. But actually there's no need to go to the 7,000rpm red-line as the best work is done as it passes one notch below that. There's plenty of torque over a big swing of the dial, little lag and a transmission that's smooth and alert under full or part load.

The full-option chassis can certainly adapt itself to a huge range of demands. Its control through corners doesn't compromise the ride, which is nicely cushioned across urban potholes and broken fast roads.

On motorways and A-roads, the steering has a well-defined movement off centre and helpful weighting so it's easy to hold your lane. Which renders the available lane keeping assist system more or less superfluous.

Tyre noise is low too. The door glass is frameless, and at German speed you do get a rustle of wind noise - but on UK motorways it isn't gong to be much bother.