Almost 60% of BMW‘s 6-series range is sold to corporate customers, so it’s not a surprise that its new model boasts even better emissions as well as a host of driver-assistance technology.

Some 1000 units are set to be sold in the UK in its first full year, and BMW is also launching a 6-series coupe in October, while a Gran Coupe concept has also been revealed for future production.

The brand has simplified the convertible range, offering two petrol engines, a 3.0-litre 320hp 640i and a 4.4-litre 407hp 650i. A diesel, which has previously accounted for two-thirds of sales, is “expected” by the end of the year.

The 640i, as tested, does 0-62mph in 5.0secs with a top speed of 155mph, yet has emissions of 185g/km and official fuel economy of 35.8mpg – not bad for a powerful sports car.

With only one trim, standard equipment includes 18-inch alloy wheels, leather upholstery, front and rear parking sensors and xenon headlights. Options include side-view cameras, lane-departure warning, active cruise control and adaptive drive.

This is a head-turning car that doesn’t disappoint. Its absorption of bad road surfaces is impressive, and it is a relatively quiet drive with the top up or down. The six-cylinder engine takes a while to pick up at low speeds but top-end power more than makes up for it.

It’s an expensive car at £65,310, but cheaper than its rival the Mercedes SL350 at £67,515. It also beats its German counterpart on CO2 with the SLK coming in at 226g/km, which results in a BIK banding of 35% compared with 27% for the 6-series.

There’s no doubting that for many fleets this car is not an option. For those that can get away with such extravagance, this 6-series is a fairly practical yet very enjoyable choice.

BMW 6-series convertible
640i SE 2dr convertible
P11D price £65,310
Model price range £65,310-£73,430
Depreciation £44,485
Fuel £9827
SMR £3408
VED £700
National Insurance £7300
Cost per mile 135.07
Fuel consumption 35.8mpg
CO2 (tax) 185g/km/(26%)
BIK 20/40% per month £283/£566
Service interval variable
Insurance group 50
Warranty 3yrs/unlimited mls
Boot space 350 litres
Engine size/power 2979cc/320hp
Top speed/0-62mph 155mph/5.7secs
On sale March 2011
Score 8/10
Verdict Class-leading in
emissions and emotion