In these days of risk-averse design you have to feel BMW deserves huge credit for taking such a radical and potentially polarising approach to the styling of its latest four-seater fastback. Love or hate the looks, one thing is for sure: that gawpy grille will seem positively tight-lipped compared to the huge grin on your face the first time you drive a 4 Series M Sport Coupe.      

Although it is based on similar underpinnings and employs many of the same powertrains as the latest 3 Series, the Coupe features additional body stiffening, a lower ride height, a wider rear axle, and more direct steering. 

Primarily, it is the exceptional levels of torsional rigidity that endows the 4 Series with exceptional driving talents. 

It may not be the sexiest of subjects but stiff underpinnings are essential to a car's ability to ride, corner, brake, change direction, suppress undesirable harshness and vibrations and, well, you get the picture. 

Given this exceptional starting point, some may argue BMW's engineers needn't have pushed the handling envelope as far as they have over the comfort quotient, but even working within the constraints of a tightly sprung M-Sport suspension the 4 Series deals with most surface imperfections very impressively indeed. 

Yes, a degree of rear axle agitation is evident - even when driving over relatively smooth surfaces - but this is offset by minimal amounts of impact aftershake, so the overall impression is one of exceptionally refined suspension management. 

You can minimise impacts even further by selecting the M Sport Pro package, which brings adaptive damping and a selectable softer-riding comfort mode. This undoubtedly brings out the best in the 4 Series, delivering superior ride quality with no tangible loss of grip or precision. That said, at £2,500 it's not a cheap option, or a totally perfect one for that matter, as the sportier setting unleashes a ride so firm it is close to unusable on UK roads. You pay your money.

Regardless of suspension option, road noise remains impressively well isolated, while those frameless windows and A-pillar mounted rear-view mirrors appear to generate little or no detectable increase in wind turbulence compared with the 3 Series saloon. 

The engine line-up ranges from truly impressive to absolute cracker.

The entry 184hp 2.0-litre is particularly refined with a velvety idle and a smooth linear pick-up throughout the rev range, and it's no sluggard either, with a gentle ease of the gas pedal releasing a surprising brisk turn of pace.

Of course, this kind of performance is made to look like a pensioner queuing at a post office compared to the M440i. Featuring a turbine-smooth 3.0-litre turbocharged petrol engine developing a thunderous 374hp, it is as well that BMW has fitted four-wheel drive as standard to provide the levels of grip and traction this kind of power output demands. 

Back in the real world, the 2.0-litre diesel is a particular gem, generating a vibrant 190hp and 400Nm of torque. It's aided by a 48V mild-hybrid system, providing engine-off coasting at speed, smooth stop-start events, and an occasional 11hp boost from the electric motor. In practice, it is a quiet, smooth and extremely tractable engine, capable of sparkling performance along with low-60s mpg.