Steve Davies

When you're up against a product such as BMW's MINI, you need to pull out all the stops in order to differentiate your own luxury sub-compact model - at least that's what Audi thought when it introduced its A1 last year.

I must admit I've never been a fan of the gullwing doors on the SLS AMG, they add complexity where it really wasn't needed and distract from the SLS AMG's virtues as a driving machine. The New SLS AMG Roadster, that Mercedes officially revealed this morning, returns to a more purist design with the added bonus of releasing more of the AMG 6.3-litre V8's wonderful sound for the enjoyment of its driver and passenger.

It 'really' is another week, another Porsche - since this is the 3rd week in a row that the Stuttgart sports car manufacturer has launched a new product - this time its an all-wheel drive version of the 911 Carerra GTS which went on sale in two-wheel drive form last December.

To mark the 50th anniversary year of the iconic DB4GT Zagato, Aston Martin has announced an exciting new collaboration with the renowned Italian design house Zagato - starting with a car to be shown for the first time at the famous Villa D’Este Concours on 21st May 2011, with a racing debut at Nürburgring later in the month.

To celebrate the 35th anniversary of the original hot hatch, Volkswagen has announced the first details of the latest special edition Golf GTI model – the Golf GTI Edition 35. With an increase in power of 25 bhp over the ‘standard’ car, the Edition 35 develops 232 bhp and is the most powerful production Golf GTI to date.

Another day, another Porsche "special edition", but haven't we been here before? Earlier this year Porsche introduced the 911 Black Edition - a base 911 wearing a party frock, then the Boxster S Black Edition with a 10 bhp upgrade over the regular Boxster S and now the Porsche Cayman S Black Edition - which true to form is a slightly more powerful - up to 326 bhp - and much cooler than the regular Cayman S.

Vauxhall are offering a £250 upgrade on its top-of-the range VXR Insignia which de-restricts its engine management system, allowing the car to achieve 170mph - although presumably not whilst heading along the M1 motorway near the company's Luton HQ.

Like me, it probably hadn't occurred to you that in order for Mercedes to create a roadster version of its popular SLS AMG, it would need to lose the gullwing doors. Okay, it sounds obvious now that I've said it, but it still seemed something of a surprise to hear Mercedes announcing as a revelation that the SLS AMG Roadster had proven to be stable even without the gullwings.