Motoring / Road test: A most exciting saloon: Powerful and practical, the Mercedes C36 is adding a dash of athleticism to the mark's staid image, says Phil Llewellin

The Mercedes-Benz C36 AMG, a powerful and discreetly dressed-up version of the C-class saloon, is a significant step in the right direction for Mercedes. The marque, despite its great sporting heritage - which includes winning Le Mans as recently as 1989 - and an unrivalled reputation for engineering excellence, has a staid, middle-aged image. The C36's mission is to do for it what the M3 and M5 do for BMW.

Like them, it combines breathtaking performance with the more down-to-earth features that make a car suitable for taking children to school and loading a week's shopping into the boot.

AMG is a German engineering operation that specialises in making Mercedes look a little different and go a lot faster. The relationship used to be strained, allegedly because Mercedes disliked the idea of outsiders daring to suggest that its products could be improved, but AMG has been part of the family since 1991.

Modified versions of mass-produced saloons can leave much to be desired, but this variation on the C-class theme is hard to fault. The external modifications give the C36 a strong, athletic character without being ostentatious. They complement lowered suspension and alloy wheels shod with ultra-low-profile tyres that would not look out of place on a racing car and could be mistaken for nothing more cushioning than circles of black paint.

Fortunately, superb chassis engineering illustrates the critical difference between an acceptably firm, sporting set-up and the sort of ride that makes your eyeballs rattle. More grip than most drivers will ever need enables good use to be made of the inspirational six- cylinder, 3.6-litre, 280bhp engine. Smooth, responsive and not too thirsty, it drives the back wheels through a four-speed automatic transmission. Automatics tend not to be associated with mettlesome cars, but the extent to which this one lessens your driving pleasure is minimal.

Those who stick the 'anti-social' label on all powerful cars should experience this Mercedes. Used properly, such as when overtaking a long vehicle, vivid acceleration is as desirable a safety factor as the anti-locking brake system's efficiency.

On the other side of the balance sheet, it is almost a crime not to equip a pounds 38,250 car with headlight washers and wipers. They cost almost pounds 400 extra. Options such as metallic paint and black leather upholstery helped to hoist the test car's price above the pounds 41,000 mark.

The driver's seat was dark and hard enough to have been carved from ebony.

Support is always preferable to sag, of course, but I never managed to get myself completely comfortable, despite just about every one of the seat's components being fine-tuned with the aid of electric motors. The rear compartment provides plenty of headroom, but overall comfort depends on the length of the passengers' legs and the position of the front seats. Separate heater controls for each side are an admirable feature, as drivers and passengers often prefer different temperatures.

The Mercedes-Benz C36 AMG would be enormously enjoyable as a two-seater convertible. The fact that it will comfortably transport a family with holiday luggage can be regarded as a bonus.

There are few stronger contenders around for the title of the world's most exciting saloon car.

SPECIFICATIONS Mercedes-Benz C36 AMG four-door saloon, pounds 38,250 Six-cylinder petrol engine, 3,606cc; 280bhp at 5,750rpm. Four-speed automatic gearbox. Performance: 0-60mph in 6.5 seconds, top speed 155mph.

Fuel consumption 24.8mpg. Headlight washers pounds 400 extra.

COMPARISONS BMW M3, pounds 32,450 Slightly smaller than the Mercedes, so feels even more agile if you can manage with less space. Important plus points include six-cylinder, 286bhp engine.

Jaguar XJR, pounds 45,450 One size and class up from the Mercedes - as is the superb BMW M5 - but this stylish newcomer must be considered.

Traditional walnut-and-leather luxury goes hand-in-glove with Ferrari-like performance from the supercharged 4.0-litre, 326bhp engine.

Saab Griffin, pounds 30,995 Sweden's contender looks staid in this company, but performance is impressive thanks to the turbocharged, 2.3-litre engine.

Price is another reason for short-listing this swift Saab.

Audi 56, pounds 34,211 Lacks the panache of a C36 or M3, but the value-for-money factor is a big attraction. The spacious Audi's tempting specification includes a five-cylinder, 20-valve engine, four-wheel drive and a six-speed gearbox.

(Photograph omitted)