Automatic superminis: what's important? - Do your research first

Picking a good supermini and specifying an auto or semi-auto 'box is often not the best approach.

The Mini One, for example, is a great car in manual guise, but go for the CVT auto option and you might regret it.

Apart from costing you an extra £1085 to buy, fuel economy will plummet by 18%, and you'll be chucking out around half a tonne of extra carbon dioxide every year (about the same as a flight to New York). You'll also lose a fair bit of performance.

Go for the Fiat Grande Punto 1.4 Dualogic and the story's very different.

It'll cost you an extra £700 over the manual version, but you won't lose any performance and fuel economical is actually better than the manual.

You'll also be emitting less carbon dioxide - albeit only by 4%.

Modern semi-automatic gearboxes, such as Fiat's Dualogic and Renault's Quickshift, offer similar, if not improved, fuel economy and emissions.

They can be used as fully automatic gearboxes or as clutchless manuals, depending on your mood.

However, remember that buyers don't normally opt for small autos because of their superior fuel economy - they buy them because they specifically want or need an automatic transmission.

Choose wisely, though, and you could reclaim some of the cost of an auto gearbox back in fuel savings.

That said, you'd have to drive 225,000 miles to recoup the £700 of a Dualogic 'box on a Fiat Grande Punto, and that could take around 20 years!