Both petrol and diesel engines are available, kicking off with a 1.6 litre petrol with 102bhp. It’s not the most exciting engine in the line-up and doesn’t really go with the A3 Cabriolet’s upmarket image, but it is the cheapest model and returns a useful 40mpg. For more enjoyment go for the 1.8 TFSI. As the name suggests, this engine is turbocharged, producing 160bhp.

It’s a swift and refined engine with a good turn of speed: 0-62mph comes in 8.2 seconds and it has a top speed of 135mph. The 2.0 TFSI – which again is turbocharged – has a real spark about it and is powerful enough to be compared with some of the hottest hot hatches. There’s 200bhp on offer and it will sprint to 60mph in 7.4 seconds and onto a top speed of 144mph – which puts it into a similar league as the VW Golf GTI.

The diesels – a 1.9 litre and a 2.0 litre TDI – bring useful fuel economy and pleasing performance. Both will return in excess of 50mpg. In July 2009 the dated 1.9 litre diesel was finally replaced by a common rail 1.6 TDI which is far smoother and quieter. It manages the 0-62mph sprint in a respectable 12.2 seconds (slightly quicker than the 1.6 litre petrol) but most impressive is its 66mpg fuel economy and low emissions – helped by a clever start-stop system which automatically cuts the engine in traffic and then restarts it again when needed.

It’s not that sprightly but does offer smooth in-gear acceleration and will happily keep up with fast flowing traffic. This start-stop system was fitted to the 2.0 TDI 140bhp engine (with the manual gearbox) in November 2009 and sees economy improve from 53mpg to 61mpg while emissions drop from 139g/km to 119g/km of CO2, bringing significant saving in running costs.

The larger engines have a six-speed manual gearbox, while the 1.6 litre petrol and 1.6 TDI models have a five-speed. An automatic gearbox which uses two clutches to provide super fast shifts is available as an option. Called S tronic it has six speeds expect the version on the 1.8 TFSI model which has seven. To boost appeal in 2010 for the open-top A3, the 1.2 litre TFSI petrol engine was added to the line-up.

This is the same engine that was recently introduced in the VW Polo and Skoda Fabia. The new 1.2 litre TFSI is a great piece of technology. It comes with 103bhp, can go from 0-62mph in 12.2 seconds and has a top speed of 118mph. It has more than enough under the bonnet when overtaking slower traffic thanks to 175Nm of pulling power.

Whether in town or out on the open road, the A3 Cabriolet is good to drive. It’s a great all-rounder with accurate steering and there’s very little body roll when cornering, plus it grips the road well. It’s compact and easy to drive in built-up areas – the steering is light, which helps with parking and three-point turns. On A and B roads it changes direction quickly and it’s possible to make fast progress when you need to.

It’s good on the motorway too – it’ll cruise happily, yet is still agile enough to change lanes with precision. The ride is smooth and will cope well with most road surfaces.