Road Test: Bags of muscle in an elegant frame: Audi's 100-series S4 luxury estate combines serious load-carrying capacity with the performance of a supercar, says Roger Bell

SUPERCAR or family holdall? Audi's 100 S4 estate contrives to be both. Its wind-cheating body is shared with lesser front-drive 100 estates that start at pounds 19,170. But the underpinnings - mighty turbocharged engine, six-speed manual gearbox and sophisticated four- wheel drive - are from Audi's steroid unit. So is the price tag, just on the wrong side of pounds 34,000.

Combining the practicality of a humdrum Volvo with the dynamic qualities of a Porsche, the S4 estate has few peers as a luxury goods express. There are no skull-cracking protrusions on the high-lift tailgate, which opens on to a large (44 x 42in) carpeted deck that can be extended to about 6ft in length by folding the split back seats.

Chromed tie-down eyes, a pull- out blind to hide luggage, a cubby- housed first-aid kit and a 'secret' under-floor locker are part of the package. An additional row of rear- facing kids' seats is extra.

Up front, the opulence of the S4 (also available as a saloon) is exquisitely executed, but not exactly welcoming. Even so, Audi uses polished timber embellishment to better effect than BMW or Mercedes - rivals in the uppercrust estate market - and the elegant cowled dashboard is notable for its classy black-on-grey instruments.

Although comfort is a strong suit - the front seats cosset more than the firm suspension - it is as a performance car that the S4 excels. Like all turbos, it pulls meekly when ambling. As the revs soar, it accelerates effortlessly. The only estate that can match it in this respect is its lighter, S2 sibling, based on the 80 series and powered by the same engine. Driven with restraint, the S4's engine is very smooth and quiet; only when extended through the gears does its strident double- edged snarl start to intrude.

Four-wheel drive and generous tyres deploy the S4's formidable power with impunity. No family five-seater comes with greater active safety - that is, the ability to avert trouble through dynamic prowess. It is virtually impossible to spin the wheels under power, or lock them when braking (an anti- skid system is standard), so the risk of losing control is minimal.

If the S4 estate disappoints, it is not in what it does, but the way that it does it. Audi has failed to recapture the tactile magic of the original Audi Quattro - one of the great landmark cars of the Eighties - in any of its high-performance progeny. What's more, you have to pay extra for things such as air conditioning, an adjustable steering wheel, even decent security. A fine car, then, if not quite a great one.

COMPARISONS

BMW 53Oi Touring, pounds 31,600. First-class comfort rather than the ultimate in space efficiency. Smooth and refined 3.0-litre V8 engine gives strong rather than exciting performance.

Citroen XM 3.0 V6 estate, pounds 27,185. European estate cars don't come roomier than this. Very comfortable, well-equipped car powered by effortless V6 engine.

Mercedes-Benz 320TE, pounds 34,800. Pricey, more practical than Audi S4, less interesting to drive. Fine new 3.2-litre six-cylinder engine. Solid and beautifully made but marred by some irritating controls.

Volvo 960 estate, pounds 27,995. Big barge of an estate that's well made, and quite lively. Comfort and safety strong suits.

SPECIFICATIONS

Audi 100 S4 estate, pounds 34,094. Engine: 2226cc, five cylinders, two camshafts, 20 valves, 230bhp at 5900rpm. Transmission: six-speed manual gearbox, four-wheel drive. Performance: top speed 140mph, 0-60mph in 6.5 seconds, fuel consumption 20-25mpg unleaded.

(Photograph omitted)