Inside & Out:
It's a strange one this; somehow adding a pair of extra doors to the 6 Series has turned a rather bloated and garish coupé into one of the world's most striking and elegant GT models. Be in no doubt, the longer wheelbase and sleek roofline mean this car is a world of visual want. On the 20-inch alloy wheels of our M Sport example we doubt there is a more striking BMW currently on sale.
The same phenomenon has been going on inside too; the previously disappointing dashboard layout and construction (seemingly at odds with the car's sporting pretensions) suddenly just 'works'. That water-flow inspired centre console now looks much more elegant and in keeping with the Gran Coupé's more subtle image and ambience. And while there's not as much room in the back as in a traditional 5 Series saloon, there is enough to make the Gran Coupé an occasional practical proposition.
Ride & Handling:
We're not sure of the cause, but whatever it is the end result is one of the most engaging handling cars in the whole of the BMW range. Despite its weight, turn-in is sharp and the Gran Coupé displays a nimbleness that belies that extended size. Clichéd or not, this is a car that, through the bends, simply shrinks around you.
Partly, that has to be down to the feelsome steering, which communicates everything happening at the end of the rack with your fingertips - though some might find the girth of the wheel's rim a little too much. There's just enough body roll to continue with that communication, making it perfectly clear when you're about to broach the limits of this car's considerable grip.
The benefit of the longer wheelbase, along with the improvement in ride quality over a 6 Series Coupé, is that with the safety systems switched off the better balance makes any slide easier to catch and, if you have the skills, ride too. In short, here's a car that manages to mix a comfortable ride (let down only by the run-flat tyres thumping noisily into potholes) with the response of a proper sports car - it really is that much fun.
Engine & Transmission:
There was a time when those looking for a performance car couldn't have brought themselves to even consider a diesel, but time (and technology) has moved on somewhat rapidly since then. The result is that now some of the quickest real-world performance cars now sport a 'd' badge somewhere on their rumps, and the 640d Gran Coupé is no different.
Consider if you will, a BMW M5, with economy in the real world considerably below its quoted 28.5mpg figure, which sprints from 0-62mph in a forced-induction fuelled and synthetically sound adjusted 4.4 seconds. That's quick, don't get us wrong, and the turbocharged V8 has diesel-like levels of low-down torque, making its 680Nm at the same 1,500rpm that the 640d manages its 630Nm. But that's the rub, there's really not much in it; despite the seemingly chasm-like 247hp deficit between the pair the 6 Series is only one second later in hitting 62mph from rest. On the road it might not be quite as frantic or exciting, but we'd wager the Gran Coupé wouldn't lose sight of its high-performance brother either.
The slug of low down torque is immense in the 6 Series, and there's a real kick as you're forced back into the plush leather sports seats. It continues through the rev-range too, the 640d not making its peak power until hitting a relatively high (for a diesel) 4,400rpm. And fitted with the eight-speed automatic gearbox, including shift paddles behind the wheel, it's easy to make the most of the performance on offer. No matter your road speed there's a gear with the perfect engine speed to match whatever you ask of it. Best of all it even sounds good while its doing it - sure you can tell it's a diesel, but the engine note is far more cultured than you'd expect.
Equipment, Economy & Value for Money:
There's no getting away from the fact the 640d M Sport Gran Coupé is a lot of money, and for many that's reason enough to demote its value rating right down the scale. However, look past the purchase price and the big GT does its best to offset this through the running costs. Real world economy is easily north of 40mpg, annual road tax only £135 and with the firm's Service Inclusive package five years of maintenance is just £400 - transferrable between owners.
That last part is one of the reasons that resale shouldn't be too painful either - and certainly the current generation 6 Series looks to be holding its value better than the previous. Compare it to the BMW M5, which costs a similar amount to purchase, and you'll visit the petrol station at least twice as much, pay three times more for annual road tax and £1,000 for the Service Inclusive package. In that respect this 640d Gran Coupé looks rather good value.
