BMW 8 Series review

The M850i has a new, cleaner-running and heavily powered-up version of BMW's 'regular' 4.4-litre V8 - and its 530bhp and epic thrust are absolutely nothing to be sneezed at. The upper half of its rev band is solid nourishment, pulling like Jupiter's gravity to somewhere beyond 6,500rpm. Albeit it operates without the audible spice of the M V8, or AMG's, despite the fact 'Sport' mode both opens the exhaust flaps early, and switches on loudspeaker enhancement of its voice.

Lower down in the revs, its manners are nicely discreet for below-the-radar mooching. It's laggy below 3,000rpm, but the smooth autobox is responsive enough to paper over the cracks. At those revs a distinct V8 rumble will stimulate your inner petrolhead, but it's not so loud it'll annoy the general population.

In full cry the suspension and steering will chomp their way down a difficult road at a crazed rate without batting an eyelid. Clearly a lot is going on down there to shepherd and marshal the 1.9 tonnes, but from your seat the effort is well disguised. Adaptive damping, four-wheel steering, active-anti-roll… yet it doesn't feel like a computer synthesis. It's just like a well-sorted car a couple of hundred kilos lighter.

The four-wheel-drive system favours rearward distribution in Sport mode, and in the rain the M850i becomes a pretty snaky customer if you loosen (let alone disengage) the traction control. Keep things in the comfort mode and it's protective and super-secure.

Throwing it around like that, you'd feel even more confident if the steering carried a little less squidge and a little more feedback. There's nothing wrong with its gearing, but even once you're on lock it always carries an initial softness.

No doubt next year's M8 will be sharper, but for now the M850i is a GT in character and maybe this isolation is deliberate. By the same token, tyre noise and sharp bumps are only distantly bothersome.

The brakes are plenty powerful for quick road driving. Like the suspension they feel natural despite a lot of tech behind the scenes – they're effectively a by-wire system.

The 8 Series can be had with most of BMW's advanced driver aids – steering assist on motorways, and very advanced cruise control. But the switchgear and warning lights make the handover from the car to the driver occasionally confusing. Use with vigilance. For long night drives, the optional laser headlights are just the business.

For really long motorway hauls, you're going to want the diesel. Its 0-62mph time still begins with a four, and driving with sense you'll be taken an easy 500 miles before fuel. Your bladder will give out sooner.