IF there`s one thing most people don`t like about four-wheel-drives, it`s that they don`t handle like sports cars.

Funny that.

In fact the whole Australian 4WD phenomenon leaves most sane people a bit bewildered. They are more expensive to buy and to run (sometimes by double) and in about 95% of cases don`t even get off the bitumen.

Toorak tractors some call them.

The problem is, it`s hard not to love them when you drive the likes of BMW`s X3, the newcomer to the so-called "Sports Activity Vehicle" class.

Firstly, the badge is one of the world`s finest, renowned for quality and innovative technology.

Take the xDrive all-wheel-drive system that debuts with this model.

The press kit sums it up well: "xDrive allows infinite, fully variable distribution of drive forces between the front and rear axle, the system immediately recognising the need for a change in power distribution and responding extremely quickly to such a change, in usual road-going situations generally before the wheel even loses its grip. This enables xDrive to transmit optimum drive power to the respective axle at all times even when taking a bend at speed, significantly reducing over- and understeer in the process.

"On the road xDrive offers a significant improvement of agility, driving pleasure and safety all in one. Suspension control systems such as DSC are not required until a much later point in time than on a conventional all-wheel-drive vehicle, and xDrive guarantees better traction and driving conditions on rough or slippery terrain, since engine power is transferred almost instantaneously to the wheels with more grip as soon as a wheel is about to spin, thus reliably interrupting the flow of traction."

The xDrive system is assisted further by a wide range of standard BMW electronic chassis safety systems such as Dynamic Stability Control III, anti-lock brakes, Dynamic Brake Control, Automatic Differential Brake, Hill Descent Control and Cornering Brake Control.

It`s hard to tell, of course, just how well the X3 would handle without xDrive (and all the rest of the fruit), but with it the result is amazing. You can practically drive this thing like a sports car. Well maybe not a sports car - family car then. In fact, this writer would go as far as saying the X3 has better handling and roadholding that 90% of the front-wheel-drive cars on the market.

It`s a great evolution from its bigger brother, the X5, which continues to receive critical acclaim from around the world. If you're trying to work out how big the X3 is, it`s about halfway between a 3 Series sedan and the X5.

The five-door, five-seater X3 comes with a tempting selection of options including the full-size Panorama Roof, Adaptive (Bi-Xenon) headlamps, Sport package, aluminium running boards, 17 and 18-inch light alloy wheels, electric front seats, sports seats, heated seats, satellite navigation and TV monitor, voice activated controls and a professional quality HiFi system.

Standard equipment includes ten airbags, multi-function leather-wrapped steering wheel with cruise control, 17-inch light alloy wheels, roof rails, rain sensor and automatic headlight control, fog lights, climate control air conditioning, on board computer and CD radio.

Depending on the configuration of the seats, up to 1560 litres is available, while up to 500kg can be carried inside. BMW has engineered the X3 2.5i to be able to tow a braked trailer weighing up to 1700kg, while the 3.0i version can tow up to 1800kg.

The X3 2.5i comes with either a six-speed manual or a five-speed Steptronic automatic transmission that offers the sporting option of manual sequential changing.

BREAKOUT

In practice xDrive provides any required shift of torque and drive forces between the axles with maximum efficiency in the shortest possible time.

A few examples:

--When setting off in normal driving conditions, the multiple-plate clutch remains almost completely locked until the X3 has reached a speed of approximately 20 km/h, thus ensuring maximum traction at step off. Then the system distributes engine power fully variably between the rear and front axle as a function of driving conditions. At speeds of 180 km/h or more (in the Northern Territory or where legal), the X3 is driven exclusively by its rear wheels.

--In bends re-distribution of drive occurs within split seconds to cut any under- or oversteer. In oversteer conditions in a bend, xDrive will close the multiple-plate clutch even tighter, feeding more power to the front wheels. This allows the rear wheels to build up greater side forces and the vehicle will be stabilised. Interacting with DSC, in turn, xDrive is able to detect any risk of oversteering at a very early point in time, intervening before the driver even recognises the change in driving conditions. DSC Dynamic Stability Control does not intervene until variable drive distribution alone is no longer sufficient to eliminate the risk of oversteer.

--During understeer-inducing conditions exiting a bend, xDrive is fed data from the DSC and offsets understeer by reducing drive to the front wheels. In extreme cases, the X3 may switch to 100 percent rear wheel drive. If even this is not enough, DSC will take over. This gives the driver 3 Series sedan levels of grip and poise especially over demanding, twisting roads. xDrive can cope with abrupt full-throttle on or throttle off conditions without the slightest problem. While the lag between the driver flooring the throttle and the engine building up power is 200 milliseconds, the xDrive multi-plate clutch is able to open or close completely within just 100 milliseconds.

--When driving with a large steering angle and under low engine power for example, when parking all-wheel drive becomes rear-wheel drive, with all the power of the engine going to the rear wheels. This avoids any axle wind-up or extra loading on the steering.

--On slippery gradients, a locking up action connecting the front and rear axles prevents individual wheels from spinning. Hence, DSC is required to reduce engine power or apply the brakes only under far more difficult driving conditions. Then, when accelerating again, the locking action of xDrive serves additionally to significantly reduce the risk of losing longitudinal or lateral forces on the various wheels, giving the driver a much safer and more agile driving experience.