A luxury SUV that makes a lot of economic sense

Are you sure what you want from your next car? That may sound like a daft question, but unlike most other consumer goods a car is a curious blend of image, functionality and cost.

There are the lucky few who can choose whatever they want and hang the expense, but for us normal people we have some difficult decisions to make. Not surprisingly, the rise and rise of the SUV is down to its practicality, driving position and yes, image. BMW already has a few offerings in this camp, although as ever, a focus on keeping a high level of driving dynamics has led the German firm to label them SAV – Sports Activity Vehicle.

Now the one that started it all has been given a new lease of life.

The X5 was BMW's first take on the SUV, and its second-generation model launched in 2007 has sold more than 15,000 vehicles in less than three years, but there's now a lightly-facelifted version with even more to offer.

Visually the emphasis is on the word 'light'. Unless you're a real nerd, you'll probably take one look, think it looks smarter somehow but not be sure why. There are new front and rear bumpers with bigger air intakes, more body colouring where before there was matt black, as well as a larger choice of paint hues and tweaked light clusters, with LEDs front and rear.

Some might be miffed that it doesn't look significantly different, but this is a mid-life tweak that won't upset current owners nor alienate potential buyers: after all, the X5 is as taut and handsome as it ever was.

That also means it's no bigger inside, but that's not an issue either.

The generous footprint means space isn't an issue, whether you choose a five or seven-seat version. Like comparable BMWs in this price bracket, luxury is the order of the day and leather seating all round now comes as standard, adding to the quality of the cabin. You can take the usual high-standard of fit and finish for granted: There's no penny pinching in here, and the X5 now gets access to all the electronic toys that have recently appeared elsewhere. The latest generation of the i-Drive controller already seen on 5-Series is feature-packed yet a cinch to use. There's also even smarter stuff like the brilliant Side View camera system that allows you to peek up the road from junctions, speed limit information automatically read by cameras, the Top View reversing camera and active cruise control, which now has a stop and go function. Effortless to use, it turns crawling traffic jams into an opportunity to sit back and relax.

Yet the real headline-grabber for the revised X5 is what's going on in the engine room. The four engine options, two of each fuel, are either new to the X5 or heavily revised. The petrols, especially the xDrive50i will be a hoot to drive, but it's the diesels that are most relevant in the UK. The xDrive30d now has four per cent more power and torque and cuts its 0-62mph time by half a second, yet it also offers 10 per cent better fuel consumption and emissions, as well as being EU5 compliant.

The xDrive40d supersedes the 35d, and although it continues with its 3.0-litre capacity, but higher pressure injectors, the full complement of Efficient Dynamics measures and lighter weight gives it a major boost over the outgoing version. Seven per cent more power and 3.5 per cent more torque result in a 0-62mph time of just 6.6 seconds – outrageously quick for a diesel car of this size that can also deliver a remarkable 37.7mpg and just 198g/km of C02. Inevitably helped by the excellent new eight-speed automatic transmission as standard, the xDrive40d has all the bases covered.

Functional driving requires very little effort from the driver: the automatic gearbox uses all eight ratios to keep engine revs low for economy and noise but also leaves it right in the middle of the torque band, so progress is smooth and unfussy. A more determined squeeze of the throttle brings a more vocal but not unpleasant sound from the engine room, while full on performance can be controlled by activating the Sport mode and taking manual control of the transmission. It may be a sizeable and weighty vehicle (although lighter than virtually all its rivals) but at some point you will want to press on and enjoy the sharp responses and impressive composure that the X5 displays. It's suspension is not the softest, but it's more than capable of riding comfortably, and the pay off is the kind of sharpness that makes brisk drive a real pleasure.

As a jack of all trades, the X5 ticks more boxes than you could reasonably expect: quick, comfortable, luxurious, responsive and efficient, wrapped up in a sophisticated package. But the real bonus with the revised X5 is that it makes more economic sense than ever, allowing you to revel in its abilities whilst totting up the fuel savings. If only life was always this effortless.