Key Facts
Model tested: BMW 435d xDrive Coupé M Sport
Pricing: £43,900 basic; £50,330 as tested
Engine: 3.0-litre turbocharged six-cylinder diesel
Transmission: eight-speed automatic, all-wheel drive
Body style: two-door coupé
Rivals: Audi A5 Coupé, Mercedes-Benz E-Class Coupé, Porsche Cayman
CO2 emissions: 146g/km
Combined economy: 50.4mpg
Top speed: 155mph
0-62mph: 4.7 seconds
Power: 313hp at 4,000rpm
Torque: 630Nm from 1,500- to 2,500rpm
In the Metal: 
The 4 Series in Coupé format is arguably BMW's most handsome machine at the moment. Viewing it from the front three-quarters, it looks big and imposing, yet also lithe and curvaceous. M Sport spec, gorgeous '442M' 19-inch alloys (£670) and a strong colour do it plenty of favours but even SE models are appealing. Inside it's wonderful too, with enough room in the back to make it a genuine four-seater and not just a 2+2. Overall, the general ambience and environment 4 Series Coupé occupants find themselves within is beyond reproach.
Driving it:
One gander at the on-paper stats is eye-widening stuff, even in this day and age of 355hp hot hatches. The 0-62mph benchmark sprint, for instance, takes a phenomenal 4.7 seconds. This is quicker than the old V8-engined BMW M3 with a manual gearbox. Cripes!
And this pub-boasting potential consolidates into road-going fervour. The 435d is seriously, seriously fast, dismissing turbo lag and using its all-wheel drive platform and super-slick eight-speed auto to summon up monster pace in an instant. It also sounds fabulous, a meaty growl and thumping exhaust note making you well aware of the rate at which you're hauling in the national speed limit. So raw speed is certainly not something the 435d lacks.
Nor does it want for grip and traction. 'Uncrashable' is perhaps a strong word but on the bone dry summer's day of our test drive, short of hammering into a 90-degree blind bend at over 60mph we're not sure how any rational human being could achieve a 435d-to-scenery interface scenario. It really is quite remarkable how something so big and with a fairly long wheelbase can cling on when laughing in the face of the laws of physics. It would have been intriguing to see just how impressive the 435d would be in torrential conditions; typical British seasonality, never gives you what you want. Of course, when you're not driving like you're in Gran Turismo 6, the 435 offers a stunning level of refinement, with a decent ride and hushed demeanour - thus amply fulfilling the 'frugal cruiser' segment of its design brief.
The pay-off for all this is a dearth of fun. While the point-to-point pace of the 435d is never in doubt, you're unlikely to be grinning maniacally during your time behind the wheel. There's a lot to commend about the weight and accuracy of the steering, the iron-fisted body control, its propensity to keep all four wheels on the ground for as long as it possibly can and brakes that are calibrated to near perfection. But it does feel as though anyone could elicit these mammoth abilities from the 435d within minutes of settling in behind the wheel; it's not a car in which you believe you will learn something new each and every time you drive it. Great as it is - and it's a lot better than a whole slew of quattro Audis that have emerged over the decades - we'd still advocate rear-wheel drive if you fancy yourself as a keen driver. Except... you can't have the 435d in rear-wheel drive. It's xDrive only. Damn.
What you get for your Money:
It goes without saying that if you want the top engine and top trim level in BMW's more desirable Coupé body, the 435d isn't exactly cheap. With options, the car we drove surpassed £50,000 - but then the magnitude of its performance puts it among some pretty elite competitor cars, many of which couldn't hope to offer economy of 50.4mpg. On our example, the biggest contributors to the £6,430 of options were Adaptive LED Headlights (£1,600) and the BMW Professional Media package (£1,000) - of these, the satnav is the key addition for resale purposes.
Worth Noting
The 4 Series Coupé is used as the basis for the Gran Coupé, examples of which we drove on the same day as the 435d. The GC has revised spring and damper rates to account for its extra doors (and weight), but is said to be the car that has one eye on long-distance cruising. Yet we reckon the 435d rode better than an xDrive version of the GC - which is odd.
Summary
It really all depends on what kind of driver you are. We suspect not everyone is as pernickety about total driving interaction as the diehard driving enthusiasts' corps; hence why the 435d xDrive is bound to be a roaring success. That's because it looks fantastic inside and out, goes like the clappers and has the sort of grip that can make its driver feel near invincible. It can also cruise in a cultured manner and should boast healthy residual values. But for a tiny sliver of the population - and we count ourselves among this fastidious number - who consider BMWs to still be ultimate driving machines, the 435 feels a bit lacking in sparkle. Although fuel costs are currently crippling, if you value driving pleasure we'd suggest the rear-wheel drive 435i will be your model of choice.
