Lateral thinking by the Mercedes-Benz board of directors back in the mid-1990s saw the prestigious German company taking an altogether different direction in its car design. While most players in this prestige class simply downsized a large car, the Mercedes A-Class took its own individual direction. The new shape was a correct one because it made for a much more spacious and practical vehicle.

 Such is the strength of the Mercedes brand that it can do almost nothing wrong in the minds of car owners. We have a sneaking feeling that if anyone else had attempted the shape of an A-Class it would have been a failure.

But enough of the philosophy behind the A-Class. What about the car?

This is a large car clothed in a small body and the cabin is much bigger than you would anticipate when looking at the compact external dimensions. There's good space for four adults without any real need to compromise on front-seat legroom to make room for those in the back.

Body width is almost to mid-size car standards and five adults can be carried for short to medium trips without the centre-rear occupant being too squeezed. There is a small ‘tunnel’ in the rear floor but it’s simple to sit with one foot either side of this.

Headroom is excellent in all seats, with more than enough space for Aussie Akubras.

Boot space is good, though the use of a large spare tyre to suit the demands of a tiny number of Australia drivers means it misses out on about 60 mm of added depth. The boot is easy to load through a big hatch and the regular shape means it can cart surprisingly bulky items. Naturally, a split-fold rear seat further improves versatility.

Unlike the original Mercedes A-Class, which took a futuristic direction in interior styling, the new generation is noticeably more sedate. Indeed, you could mistake the dash area of the A-Class for that of one of the bigger Mercedes saloons.

For 2009 there are detailed changes to the interior trim shape. This is chiefly to give even more stowage space for knick-knacks like phones, sunnies, wallets and so on. Bolder trim styles and a new palette of colours and materials lift the looks of the interior, though without upsetting the aforementioned sedateness of style.

The pre-facelift A-Class was already a quiet car to ride in, but a further reduction in NVH (Noise, Vibration and Harshness) was part of the latest design brief. Interior noise levels are pleasantly low and even Australia's notorious coarse-chip road surfaces don’t increase tyre/road noise to an unpleasant extent.

Riding in the small Mercedes models gives you the feeling that you are travelling in an upmarket car at least a size larger.

Larger door mirrors are part of the 2009 facelift and these have been reshaped to improve aerodynamics and thus reduce wind noise.

While the latest generation Mercedes A-Class continues to follow the overall styling theme of the original, it has a lot more sleekness and should now appeal to a wider spread of buyers. From its low nose, over the streamlined roof and down to the extra-large tail-lights it looks special and plenty will be happy to display it in their driveway with pride.

Interestingly, the brake lights will automatically activate the hazard warning flashers for a few seconds if you brake hard. Hopefully prompting dozy drivers behind you to the fact that something is happening.

Biggest news in the Mercedes A-Class is the option of a turbo-diesel for the first time in Australia. The four-cylinder engine in the A180 CDI has a capacity of 2.0 litres and puts out 250 Nm of torque over a good spread of the rev range. Peak power is apparently on the stingy side at only 80 kW, but torque is the name of the game and the engine is more than happy to pull from just about any revs and makes light work of and/or climbing long, steep hills.

Fuel consumption is likely to be in the range of five to six litres per hundred kilometres when running in the country or on motorways, and is unlikely to climb much higher than sevens when commuting in traffic. These are exceptionally low figures for a full four-seater that carries plenty of standard equipment and which is built to Mercedes' high safety standards.

The engine is obviously a turbo-diesel in its noise and vibration characteristics, but not objectionably so. Indeed, once the car is up to its cruising speed we defy most occupants to differentiate it from a petrol variant. There's some turbo lag but once it has passed the engine has good response characteristics and is pleasant to sit behind.

Handling is safe, with just a hint of understeer should you push it hard. The car has an array of electronic aids to help you out of trouble should you make a serious misjudgment. This is no sports sedan, nor does it pretend to be, rather its compromise sensibly leans in the direction of comfort.

Those who are concerned about global warming and are moving to more sensible cars should seriously consider this small-outside big-inside Mercedes A180. And if caring for the planet you live on isn’t your thing (and it should be!), then perhaps the prestige offered by the famed three-pointed star will swing you to this stylish machine.

AT A GLANCE

MODEL RANGE

A170 1.7-litre three-door hatch - $35,500

A200 Avantgarde 2.0-litre three-door hatch - $45,900

A200 Turbo Avantgarde 2.0-litre three-door hatch - $49,500

A170 1.7-litre five-door hatch - $37,900

A180 CDI 2.0-litre diesel five-door hatch - $39,900

A200 Elegance 2.0-litre five-door hatch - $47,900

SPECIFICATIONS (Mercedes-Benz A180 CDI 2.0-litre diesel five-door hatch)

ENGINE:

Capacity: 1.991 litres

Configuration: Four cylinders in line

Head Design: Four valves per cylinder

Compression Ratio: 18.0:1

Bore/Stroke: 83.0 x 92.0 mm

Maximum Power: 80 kW @ 4200 rpm

Maximum Torque: 250 Nm @ 1600-2600 rpm

DRIVELINE:

Driven Wheels: Front

Manual Transmission: Six-speed

Automatic Transmission: CVT

Final Drive Ratio: 3.24:1

DIMENSIONS, WEIGHT AND CAPACITIES:

Length: 3838 mm

Wheelbase: 2568 mm

Width: 1764 mm

Height: 1595 mm

Turning Circle: 10.95 metres

Kerb Mass: 1345 kg

Fuel Tank Capacity: 60 litres

Towing Ability: Not supplied

SUSPENSION AND BRAKES:

Front Suspension: MacPherson struts, three-link, coil springs, torsion bar stabiliser

Rear Suspension: Parabolic rear axle, coil springs, torsion bar stabiliser

Front Brakes: Ventilated disc

Rear Brakes: Disc

PERFORMANCE:

0-100 km/h Acceleration: 10.8 secs

FUEL CONSUMPTION:

Type: Diesel

Combined Cycle (ADR 81/01): 5.2 L/100km

GREEN VEHICLE GUIDE RATTINGS:

Greenhouse Rating: 8/10

Air Pollution Rating: 5/10

STANDARD WARRANTY:

Three years/unlimited km