According to BMW, water has influenced every aspect of the design of its new 6 Series, which goes to show what utter rubbish car manufacturers spout when it comes to their latest models. There is, according to the design boss, fluidity everywhere you care to look, from the kinks and creases of its complex body shape to the interior. Best to ignore the marketing hyperbole and the corporate nonsense; the latest 6 is a huge improvement over the outgoing model. Granted, it has nothing of the shock factor of the previous, Chris Bangle-era 6 S, which looked quite striking from the front but, by the time your eye had worked its way round to the rear, you were probably starting to feel ill. The new one, no matter what angle it\'s viewed from, doesn\'t have anybody reaching for the nearest bucket. Unusually, BMW chose to launch the new 6 Series as a convertible months before the tin-top, which has only just been unveiled, and there will be another body shape emerging next year, too, as a four-door coupé, which will go head-to-head with Merc\'s CLS and Audi\'s A7 Sportback. Nobody could accuse the Germans of stifling choice. Under the new clothes it\'s a car based on the latest 5 Series, which is as good a starting point as any. And the convertible boasts a 50 per cent increase in torsional stiffness compared to the previous drop top 6 Series. The engines, too, are new and vastly improved, with a 3L, turbocharged straight six in the 640i and a 4.4L twin-turbo V8 in the mighty 650i. There\'s good news regarding the new 6\'s interior, too, and there\'s no denying that the driver is the centre of attention when sat behind the chunky wheel. The instrumentation is angled in his or her direction, just like it was in BMWs of the 1970s and \'80s and it\'s a really well-thought-out and executed cabin crafted using quality materials. On the road, the 650i is the consummate GT car. Quiet, extremely comfortable and highly refined, there is a real danger that it could actually be a bit dull. There\'s plenty of low-down power from the twin-turbo V8 but you can\'t really hear it. And that\'s a shame because there\'s a meaty soundtrack being strangled in there somewhere. The optional (Adaptive Drive) adjustable suspension gives the car poise and excellent road-holding, with very little pitch or roll, and does a really decent job of disguising the car\'s weight. But the steering feels lifeless and uncommunicative, which is unusual because BMWs always used to feel like proper driver\'s cars. The 650i will crack 100kph in five seconds flat (top end, as is usually the case, is limited to 250kph) so it\'s a serious performer. It just doesn\'t feel like one. This isn\'t helped, either, by the new eight-speed auto \'box. It\'s a fine unit, don\'t get me wrong, but if you take over using the paddle shift, with eight ratios at your disposal, you\'re constantly changing up and down. Far better to leave it in auto mode and let the impressive torque propel you along while the car seamlessly works its way through the gears. It really is a mixed result, the new 650i Convertible. It looks better, goes better and handles better than any before it, but this progress seems to have been at the expense of driver enjoyment. It\'s perhaps telling that BMW\'s advertising tag line used to be \"The Ultimate Driving Machine\". These days it\'s all about \"Joy\". Now the company has got the styling back on track, perhaps it needs to focus next on the driving experience. Bring on the M6.