MINI Cooper SD Roadster

It might lack the raucous soundtrack of the Cooper S - but overall the diesel Roadster is a worthy addition to the range -and well worth considering if you plan to use it everyday. The playful chassis means it’s great fun to drive, too. But bigger soft-tops offer a more grown-up driving experience, and the extrovert image won’t be for everyone.

MINI has been soaring up the sales charts recently – and a big part of that success is down to its constantly expanding line-up. The Roadster is the sixth body style to join the modern range, and it’s also the first open air two-seater in the company’s history.

We were impressed by the Cooper S version of the Roadster that we drove back in January, and thought it could be a genuine rival for the class-leading MX-5. This diesel version on the other hand, promises to be something totally unique.

The Cooper SD has no real rivals at this price - with the possible exception of bigger four-seaters like the Golf Cabriolet and Audi A3 – but with 45Nm more torque than even the John Cooper Works, its blend of pace and economy could make it the pick of the range.

Visually there aren’t too many differences between the Roadster and the harp-top Coupe upon which it’s based, and the extrovert design, bonnet stripes and retractable spoiler are all bound to get you noticed. Our test car also came with the £1,195 optional Sport pack, which adds an aggressive front bumper, side sills and multi-spoke 17-inch alloys.

The simple cloth roof folds away in 10 seconds flat and even without the removable wind deflector between the chrome roll hoops, there’s very little buffeting at speed. Cruising refinement is impressive, but the big manual release handle and exposed metal ribs do feel a bit dated. The advantage of having such a basic mechanism is that it takes up less room, and doesn’t intrude into the sizeable 240-litre boot.

There’s a mildly intrusive rattle from the 2.0-litre engine on start-up, but it quickly settles down into a more refined cruise, and the combination of a low kerbweight and wide powerband is enough to make it feel really rapid in-gear.

The six-speed gearbox and quick, communicative steering mean the Roadster is also a real entertainer on twisty country roads, and the rigid chassis means that it feels much more balanced and planted than the Convertible over bumpier surfaces - even if the firm and sporty suspension setup won’t suit all convertible buyer’s tastes.

Despite this muscular performance, with fuel-saving technology like stop-start and regenerative braking as standard, the diesel Roadster boasts the same running costs as the average supermini, with emissions of just 118g/km and an economy figure of 62.8mpg.

This broad range of talents makes the Cooper SD a great alternative choice for sports car fans. But it does lack the hot hatch character of the petrol versions, so perhaps it’s no surprise that MINI predicts the vast majority of its Roadster sales will be petrol.