Porsche C4S Cabriolet

The price hike over the fixed-head 911 is hard to justify, particularly as you could buy a brand new supermini with the change. Thanks to its sleek, purposeful styling, the C4S cabriolet is certainly a head-turner, but only those who are addicted to the thrills of open-air motoring will be prepared to stump up the extra cash.

Auto Express lifted the lid with the first pictures of Porsche's new 911 Carrera 4S Cabriolet earlier this month - but what is the fastest Porsche drop-top on sale like to drive? To find out, we put one of the first examples off the production line through its paces.

Despite its appeal, the all-wheel-drive C4S cabrio has never matched the purists' ideal of a 'true' Porsche. Previous-generation cars have been criticised for lacking the standard model's feel, while the drop-tops stood accused of sacrificing chassis rigidity for extra style.

However, the latest incarnation aims to put that right. Styling-wise, the Carrera has a squat, purposeful look, with a wider body accommodating the larger 4WD axles. This hunkered-down stance is accentuated by twin exhausts. Inside, the 911 oozes quality and refinement. The rear seats are still only for children, but even the roof lining, often overlooked by some makers, is well finished. Thankfully, sun-worshippers should be able to enjoy every chink in the clouds, as the hood raises and lowers in a mere 20 seconds. And even with the top down at motorway speeds, it is so refined you can talk to your passenger. Performance is blistering, with 0-62mph taking only 4.9 seconds. Top speed is 179mph - the same as the coup