THE Land Rover Discovery, when it was launched here more than eight years ago, was almost singe-handedly responsible for the re-emergence of the British company as a significant force in the off-road market. It brought Range Rover levels of comfort and ability within the reach of mass-market 4WD buyers and carried Land Rover onto the podium as second-largest European importer in the early 1990s.

Over the years, the very capable British vehicle has endured strong competition from Japanese 4WDs but, so far, no one has yet managed to wrest the best-4WD title from Land Rover's grasp.

Best, that is, in terms of ability and design, not in terms of quality or reliability - although both of these elements are supposed to have benefited from BMW taking control of the company between 1994 and 2000.

Today, the BMW influence is still difficult to spot, although the Discovery appears better put together than ever (the doors for example are now steel rather than aluminium-skinned and show tighter panel fit) and the interiors are less eccentric if still not entirely ergonomic.

Even more difficult to spot are the styling changes in the latest-generation Discovery. Even though the people at Rover Australia tell us that virtually the only carry-over panel is the tailgate, it's not easy to quickly pinpoint the differences.

But they are there, from new grille and front bumper to new high-mounted taillights, from re-shaped windscreen pillars to flush-glazed rear side windows.

And the body is longer, despite the unchanged wheelbase, giving a noticeably more spacious rearmost compartment with two optional forward-facing third-row seats rather than the previous side-saddle affairs.

All this conceals a significantly reworked chassis and drivetrain.

Of chief interest among these is the new TD5 turbo diesel. A Rover development, this compact and efficient five-cylinder powerplant displaces just 2.5 litres, but manages to come close to the petrol 4.0-litre V8 in torque output.

Although its maximum power output is a modest 101kW (at just 4200rpm) it comes within 20Nm of the V8's torque by producing a thumping 300Nm at a very low 1950rpm.

For those disillusioned by the V8's lack of verve and its heavy thirst for fuel, the five-cylinder diesel does the job nicely, even when hooked up to the (also new) ZF four-speed automatic gearbox.

Of equal interest is Discovery's new rear suspension. Replacing the original A-bracket located system which was at the core of early Discovery handling problems is a new, Watts-link/trailing arm setup that, among other things, helps the Discovery sit flatter while cornering and allows it to track more securely over rough stretches of road.

Then there is the new air-sprung rear suspension that is standard with the seven-seat package. Similar to, but more advanced than the air suspension used on the Range Rover, the system employs air springs that are controlled by an air distributor to maintain a constant ride height under varying load conditions. For off-road use, the air springs can be used to jack the Discovery an extra 40mm to help ground clearance - in fact the system will automatically lift the rear end if it happens to ground and lose traction at low speed.

But the primary innovation on Discovery is the new "ACE" "active" suspension control. This system uses "roll control modules" front and rear that act on the suspension to virtually cancel out cornering roll before it develops. Rover says the system is able to respond to the roll forces generated by a .5g side force within .25 of a second.

And that's not all. Discovery also gets traction control, hill decent control (this automatically activates the brakes during a steep, slow, off-road descent) and the now-common electronic brake force distribution to maximise the efficiency of the anti-lock braking system.

The Discovery comes in three forms: the base model V8, the TD5 and the top-of-the-line ES - TD5 or V8 - which comes complete with leather interior, power front seats and a 12-speaker, 320 Watt Harman-Kardon sound system including a six-disc CD stacker.

The test Discovery was a TD5 optioned up with automatic transmission and seven seats - which meant it came with self-levelling rear suspension - and the ACE suspension system.

Climbing aboard, it's only too easy to find connections with the previous model. The instrument panel, despite numerous changes including steering wheel design, new instrumentation and switchgear, is not really much different to the previous design and the cabin remains light and airy, with good visibility for the full 360 degrees. The windscreen is a little higher than before, but so subtly that only regular Discovery drivers would notice.

The real differences become noticeable out on the open road.

Pushed hard on tight, twisting back roads, the ACE-suspended Discovery sat flat and secure, nothing like any 4WD of recent or past experience, while responding to the wheel more like an overgrown sports coupe than a two-tonne off-roader.

The workings of the ACE system are undetectable to driver or passengers, but the overall result certainly is: this is undoubtedly the best on-road legitimate off-roader in terms of balancing outright handling with ride quality.

And the on-road behaviour is matched by superlative off-road abilities. The technical overload of the numerous systems only adds to what has always been a most effective off-road chassis. There are few places within the normal 4WD spectrum that a Discovery wouldn't trundle through with ease.

The five-cylinder diesel does a remarkable job of propelling the heavy Discovery, but it's never about to provide dizzying acceleration off the mark or out on the highway. But its torque is strong enough to maintain speed on hills and really comes into its own on steep bush tracks.

The ZF auto is a smooth shifter, too, slurring the ratio swaps nicely and kicking down readily when asked. The only strange thing was its tendency to drop instantly back to idle when the throttle is backed off at lower road speeds - the abrupt cessation of diesel roar on such occasions is a little weird.

Not that the diesel is noisy. After warm-up, the tone drops back to a distant thrumming that is somehow reassuring rather than intrusive. And it's smooth, too, noticeably moreso than the previous four-cylinder turbo diesel although we suspect not quite as economical. Still, anything that sips less fuel than the V8 is always welcome.

Among the few annoying things were the crude cruise control (with no coast mode) and the lack, at the lower end of the range, of anything more than basic seat adjustment controls. And the front internal door handles are in a difficult-to-find, low-slung position.

So the Discovery still gets our vote as the most desirable of heavyweight off-roaders. Suspension performance, especially with the ACE suspension, are amazing and the numerous techno innovations help make an already outstanding off-road performer even more unstoppable.

It is really difficult to beat for the money.