Volkswagen Polo01 May 2009

This is the fifth-generation Volkswagen Polo and it takes the long-standing supermini to new levels of efficiency, refinement and, most obviously, size. The once diminutive city car has ballooned - it's now easily as big as a mark 3 Golf.

Yet despite the bigger road footprint, Volkswagen has managed to make this Polo lighter than the last. It's also introduced a range of highly efficient three- and four-cylinder engines, all of which combines to make the latest Polo an extraordinarily frugal family runaround.

However, VW's focus on massive fuel economy and low CO2 means the Polo arrives with some worryingly weedy engines. The range starts with two 1.2-litre three cylinder motors with either 59bhp or 69bhp and 128g/km CO2 emissions, followed by a 1.4-litre four cylinder with 84bhp. All three offer pretty bland driving and no real urgency, but will do the trick for anyone who'll spend the majority of their time pootling to the shops in their Polo.

Better is the 1.6-litre TDI diesel available with 74bhp, 89bhp or 104bhp and just 109g/km CO2. It's got more go and mid-range motorway pulling power, but the characteristics of an oil-burning engine rarely bring the best out of a supermini, and the Polo is no exception.

Our pick - and the zestiest drive - is the Twincharged 1.2-litre TSI. This 104bhp three cylinder engine is both turbo and supercharged and brilliantly blends a little performance with excellent fuel economy. It feels like it has the thrust of a conventional 1.6 and is flexible enough to impress in all circumstances, be it town, motorway or back road.

Mated to this new TSI engine, VW is offering as an option a dual clutch DSG gearbox for the first time in a supermini. It's smooth-shifting, but we wouldn't recommend it. It's expensive for a start, and seemed to strangle the zip of the little motor because it's been geared to be as green as possible. It also seems pretty ridiculous to have a seven speed DSG - you just don't need that many gears with an engine that generates just 129lb ft torque. We'd stick with the slick manual.

Anyone after the greenest and cheapest possible option should opt for the diesel Bluemotion version, out in 2010, which will be capable of an incredible 87g/km CO2. Meanwhile, for the enthusiast, Volkswagen promises a Polo GTI with the 168bhp 1.4-litre TSI under the bonnet.