Audi A1 1.6 TDI Sportback

What is it?

It's the new five-door Audi A1. Or if you're Audi marketing personnel, it's the A1 Sportback.

Beyond the inclusion of the rear doors, the differences between the Sportback and the standard A1 are fairly subtle. The C-pillar is at a steeper angle, there's over 10mm more elbow and head room in the back and the rear bench now accommodates three rather than two passengers. There's no increase in seat-up boot capacity, so that remains at 270-litres.

For all the extra usefulness, Audi will charge you around £500 more over the three-door. From launch the Sportback is available with the core engines – 1.6 TDI, 1.2 TSI and 1.4 TSI (120 and 182bhp). A 2.0 TDI and the cylinder on-demand 1.4 TSI will go on sale later in 2012. We're testing the 1.6 TDI in Sport trim (which accounts for around 60 per cent of all A1s sold).

The diesel is only available with a five-speed manual 'box and will be one of the biggest sellers thanks to its headline figures of 99g/km and 74.3mpg combined.

What’s it like?

In its own way, it's exceptionally good. We're very familiar with the 104bhp 1.6 TDI motor, and it is still our least favourite powertrain in the A1. Whilst perfectly acceptable, the slightly lethargic response and gruff soundtrack is at odds with the otherwise encouraging dynamics. It's very fit for use, it just lacks the vivacious delivery of the petrols.

Still, refinement is good and the space in the rear is marginally improved. It's comfortable for two average-sized adults. The occasional third seat is one of those things that sounds trivial but is likely to be highly valued by the small families that Audi expects to be the A1 Sportback's key audience.

We tried two diesel test cars, one with the standard sport suspension that comes with Sport, and one with Dynamic suspension – a no-cost option on Sport models that brings a slightly softer set-up, both on optional 17-inch alloys.

In truth the difference we felt over all manner of UK roads was quite minimal. Both are noticeably firm by most supermini standards, but the sport set-up had a sharper secondary ride and was particularly unsettled over higher frequency intrusions like eroded tarmac and small creases. We’d opt for 'dynamic', since the compromise it brings in terms of body roll is virtually undetectable and yet it does provide slightly more forgiving bump absorption. If comfort is a top priority, we’d strongly suggest going for the standard 16-inch wheels.

Should I buy one?

Yes, though we’d recommend any of the petrols over the rather dull-feeling 1.6 TDI unless you are expecting to cover many motorway miles. The Audi interior still falls short of the blatant style overload that is the Mini, but for those who value ergonomics that will be no bad thing.

In many ways, the Sportback actually makes more sense than the three-door A1. If you don’t count VW under the same 'premium' umbrella, the Sportback has no direct premium rivals but for the less practical Mini Clubman, and the added utilitarian value doesn’t corrupt the looks (too much) or the general likeability of the car.

Audi clearly believes the same, given that it expects two thirds of A1 buyers to opt for the five-door. If you’re intending to be one of them, you won’t be disappointed.