BMW xDrive M50d, £63,715
Engine: 3.0-litre diesel unit producing 381bhp and 545lb/ft of torque
Transmission: Eight-speed automatic driving all four wheels
Performance: Top speed 155mph, 0-62mph in 5.3 seconds
Economy: 42.2mpg combined
Emissions: 177g/km of CO2

YOU CAN’T knock success. Popularity is no guarantee of quality of course, but when it comes to parting with your hard earned there must be something in it. BMW’s X5 has been diverting people out of rival 4x4s since 2009, and the third generation model is an impressive step forward in every direction.

That’s not enough for some people, and BMW’s relentless pursuit of new niches means there’s an X5 with a very different flavour. The M50d gets to wear the coveted ‘M’ badge, which in BMW-speak means very high performance, yet it’s also powered by a diesel engine. Surely that can’t be right?

Don’t doubt it for a second. It may only have 3.0-litre under the bonnet, but the six-cylinder diesel engine has three – yes three – turbochargers in a world when two is already quite a lot. The net result is mind boggling – there’s 381bhp on offer, but more impressive is the 545lb.ft of torque, which is more than the M5 super saloon. All that power and torque is fed through to all four wheels through an eight-speed automatic transmission.

The X5 M50d is not a small car by any means and weighs a fraction of two tonnes, yet when you’re behind the wheel it is seemingly capable of routinely ignoring physics and accelerating as if it’s fleeing the apocalypse. There’s very little effort required by the driver too. Mash the throttle pedal to the floor and the X5 M50d will blast to 62mph from rest in a scarcely-believable 5.3 seconds.

When you’re not trying to rip up the tarmac, the X5’s mighty engine is a delight to use. As you might expect, there is massive amounts of torque available from very low revs, and in normal driving only a faint squeeze of the accelerator is required to make rapid progress. The six-cylinder engine is smooth and refined too, so long distance cruising is effortless and refined too.

Conversely, if you should choose to exploit all the available performance of the X5 M50d, then it does a pretty convincing impression of a sports car. Yes it’s big and tall and other things that sporty cars normally aren’t, but it’s been engineered to handle like a car should. It has enough traction to exploit all of that performance, the steering is quick and accurate and you can hustle it along at pace that shouldn’t be possible.

The X5 makes the most of its size when it comes to accommodating passengers and luggage. Those in the front have a superb view out with the much-loved high driving position, and the seats have a multitude of adjustments and are very comfortable. It’s the same in the back too, although the central seat is less comfortable than the outer two. The boot is also nice and big with a handy underfloor storage area.

The third generation X5 is a car that knows its audience very well. It has a strong image, and the more sensible diesel versions are easy to live with too. This M50d is much more of a style statement and not for everyone or every budget, but it is fast, comfortable, fun to drive and luxurious. That’s a collection of abilities that is hard to resist.