I’ve been predicting the imminent demise of the recreational off-roader for nearly a decade. Though I am fond of some, in my more lucid moments I cannot see how they can survive. But they do.

Compared with any respectable saloon costing the same money, SUVs are slow and thirsty, neither ride nor handle well, belch CO2 and as far as I can see do more to slow speeds during term time in central London than any other factor.

I’ve seen no plausible evidence to say they are safer than conventional cars and no shortage saying the reverse. You may have a lot of metal around you, but if you believe prevention is better than cure, driving a heavy car with a high centre of gravity is no way to avoid an accident. And all this just so you can look down on other road users?

One day the world will wake up, but in the meantime the BMW X5 is bucking my gloomy predictions and selling without apparent effort. Despite a four-year-old design and formidable opposition (in the shape of the Range Rover, Porsche Cayenne and VW Touareg) sales continue to soar, a trend this new X5 is likely only to accelerate.

Though it looks like a slightly less attractive version of its predecessor — as seems mandatory at BMW these days — appearances are deceptive. In its 4.4 litre form the vehicle receives a new V8 engine, gearbox and four-wheel-drive system. There’s a new 3 litre diesel, too, and come the spring a 4.8 litre motor as well. Only the 3 litre petrol engine survives in original form.

If the £47,525 4.4i Sport I tried is representative of the range, BMW has injected fresh energy into a design that already felt young for its years.

The new V8 benefits from a power hike from 286bhp to 320bhp and a cut in 0 to 62mph time from 7.5sec to 7sec. Top speed is 149mph unless you choose the slightly cheaper (£46,935) SE model, which is limited to 130mph. Despite the extra power, fuel consumption has actually improved, but if 21.6mpg still sounds sufficiently ferocious to make you think of the 3 litre petrol automatic version instead, think again. Despite an engine nearly 50% larger, and almost 90 extra horsepower, the 4.4i is a mere 0.3mpg thirstier.

The new gearbox brings a commensurate improvement to the driving experience. This box — made by ZF — is the world’s best conventional automatic, which is why it can be found under the bonnets not only of myriad BMWs but a stack of Jaguars and Audis too, not to mention the Bentley Continental GT. It brings to the X5 the same slick shift and almost telepathic ability to be in the gear of your choice.

However, while few found cause to complain about the X5’s old five-speed gearbox, its comparatively primitive all-wheel-drive system, with a fixed 50:50 power split between the front and rear wheels fared less well, leading to suggestions that the X5 was an off-roader in appearance only. The new system, known as xDrive, is state of the art, though unlike all its aforementioned rivals the X5 still has no low-ratio transfer box.

Instead there is a multi-plate central clutch that distributes power to whichever axle can best use it, and sensors on the wheels and around the car to determine in what ratio it should then be split between the wheels. BMW says the system is intelligent, a claim justified by its ability to take information about conditions underfoot and use it to predict the imminent torque requirements of each wheel. In the filthy January weather, the new X5 feels sure-footed to a fault.

But there are things this otherwise effective rejuvenation of the X5 cannot conceal. The back seat is a little cramped and the ride quality, at least of the Sport version I drove, was close to unacceptably harsh over even modest bumps and potholes. And I’d still stop short of calling it fun to drive. Porsche’s Cayenne set new handling standards for the class, and good though xDrive is, it cannot regain this ground.

It also looks expensive: the more powerful £42,770 Porsche Cayenne S has a better badge and is nearly five grand cheaper. I think I’d still plump for the BMW on looks, but neither is the best car in the class. For £50,445 — £2,920 more than this X5 — you could have a Volkswagen Touareg V10 TDI. The marque may not have Porsche or BMW’s credibility, but then they don’t have a 5 litre, twin-turbo V10 under the bonnet.

BMW is unlikely to be worried, however. With such a capable car and solid residual values, it knows it is on to a winner — and so do I now. When I rang a central London dealer pretending to want one, I was told demand was such that I shouldn’t expect it before 2005.

VITAL STATISTICS

Model: BMW X5 4.4i SE
Engine type: V8, 4398cc
Power: 320bhp @ 6100rpm
Torque: 324 lb ft @ 3700rpm
Transmission: Six-speed automatic
Suspension: (front) MacPherson struts, air springs, anti-roll bar (rear) multilink rear axle, air springs, anti-roll bar
Fuel/CO2: 21.6mpg (combined), 317g/km
Acceleration: 0-62mph: 7.0sec
Top speed: 130mph (149mph - Sport)
Price: £46,935 (£47,525 - Sport)
Verdict: An impressive update but no longer the class best