It does not snow very often in this country, but when it does there is no mistaking the owners of a four-wheel-drive car. When everyone else comes slithering to a halt, they simply glide past in safety.
Many UK buyers turn to off-roaders for all-weather reassurance, but do we need such an extreme solution? Adding a 4WD system to an executive saloon will seem obvious to Audi buyers, but in Britain, at least, rival manufacturers have not followed suit.
However, in other countries BMW's 5-Series is available with a choice of transmissions, feeding power to either the rear or all four wheels. We braved the big freeze and tried out the firm's latest 4x4 saloon to see if it could increase the blue propeller's grip on the executive car market.
The 5-Series xDrive has just been launched on the Continent, having already been introduced into the US. Its technology is an impressive engineering achievement which was showcased on the X3 and X5. Unlike most other four-wheel-drive vehicles, the 5 does not rely on oil pressure to engage all the wheels, instead employing a computer to determine where power is needed.
Using a multi-plate clutch to direct the drive where necessary is much quicker than traditional systems, and this helps make the 5-Series feel more controlled out on the road. In normal conditions, xDrive sends 50 per cent of its torque to each axle, giving excellent balance when cornering.
The £1,750 set-up was certainly impressive when we put it to the ultimate test on a frozen river. Even on ice, grip was surprisingly good, and only when we stepped out of the car did we realise just how slippery the surface was.
BMW had fitted our 3.0-litre six-cylinder 530 xi with winter tyres, which offer much better traction than the all-year rubber most Brits have on their vehicles. But even allowing for this, the model still showed a big improvement when turning into tight bends, and had plenty of grip out of corners.
In fact, if you are gentle with the throttle the 5-Series does not even engage its stability-control system, which is cleverly linked to the computer governing the xDrive. The only time you really notice the adverse conditions is under braking, when the ABS kicks in far earlier than it would on dry tarmac.
Elsewhere, the 5-Series xDrive remains unchanged from other models in the range. There are no compromises in terms of cabin space or refinement, with the extra mechanicals having no effect on the interior noise levels.
It is testament to the quality of the system that the 0-62mph sprint takes only 0.3 seconds longer than the 2WD car, and economy falls by only 0.6mpg. This puts many 4x4 rivals to shame, as mechanical inefficiencies often mean such vehicles are slower and thirstier. So would xDrive make sense in the UK? BMW has not ruled out bringing it here on the next-generation 5-Series, but the work involved in converting to right-hand drive would need to be factored in early on to make it financially viable.
For now, at least, BMW buyers have a choice between opting for an SUV, or putting up with the annual struggle for grip around this time of year.