What is it? This is the hard-top version of the latest BMW (the convertible has been on sale since March) and BMW's answer to stylish GTs such as the Jaguar XK and Maserati Granturismo.
The latest 6 promises enhanced comfort and performance but, unlike its main rivals, it's available with a diesel engine.
The diesel on offer is a new 309bhp twin-turbo 3.0-litre (which is misleadingly badged 640d). Alternatively, you can have a 316bhp 3.0-litre petrol (badged 640i) or a 401bhp 4.4-litre twin-turbo petrol (badged 650i).
What's it like to drive? All BMW Coupes come with Drive Dynamic Control, which lets you alter the way the steering, accelerator and gearbox react.
Our test car was also equipped with Adaptive Drive, a £3400 option that brings electrically controlled and adjustable suspension. However, even when this system is in its most comfort-orientated setting, the ride is a bit unsettled over broken surfaces.
The fact that our car was an M Sport probably didn't help – this trim brings bigger wheels and a lowered ride height.
Still, things get better with speed; the 6 is a refined and planted motorway cruiser. There's loads of grip in bends and you can almost completely eliminate body roll if you put Adaptive Drive in its Sport setting. Just don't expect the 6 to feel razor-sharp; it's not as agile as the lighter Jaguar XK, and the steering is short on feedback, whichever setting you choose.
The new diesel engine is much harder to fault. It delivers effortless performance, aided by an eight-speed automatic gearbox that always seems to be in the right gear. Work the engine hard, and the exhaust note is rorty rather than rough.
What's it like inside? The dashboard is identical to the Convertible's, which means it looks and feels expensive, and is user-friendly. Most systems are controlled through a central dial that's linked to simple on-screen menus, while eight programmable shortcut buttons take you straight to the functions you use most.
The driving position also impresses, because there's a huge range of adjustment and plenty of space. However, adults won't want to ride in the back for long – there's more space than there is in an XK, but head- and legroom are still tight.
The 460-litre boot is big for the class and can swallow three 46-inch golf bags or a couple of suitcases. There's a ski flap, too.
Should I buy one? While it's far from cheap, the 6 is priced in-line with rivals, and every version comes with leather upholstery, electrically adjustable memory seats, satellite-navigation and front and rear parking sensors.
Whether you should choose one over a Jaguar XK depends on your priorities: the Jag has sharper handling, but the 6 is roomier, and it averages more than 50mpg in diesel form, whereas the most efficient XK has a V8 petrol engine and can manage only 25.2mpg. The 6 can also cover 791 miles between fuel stops – 401 more than the XK.
What Car? says…
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