When BMW introduced the V8-engined M3 in 2007, it was an open secret that both a four-door saloon and a convertible model would follow shortly thereafter. We didn't have to wait too long for them and the M3 Convertible represents the latest and best in a steadily improving bloodline.

Getting a handle on the BMW M3 Convertible's back story starts with the E30 model. In 1988, BMW launched the original E30 M3 to allow them to compete in Group A racing. This was an instant hit and BMW followed it up with the rather puzzling M3 Convertible, a car that lacked the racy image and razor sharp reflexes of its tin top sibling. Then in 1993 came the more sophisticated 3.0-litre E36 generation M3 with 286bhp, the convertible version of which was a huge hit. 1996 saw the introduction of the 321bhp 3.2-litre successor, the M3 Evo, which again shifted big numbers in convertible guise. 2000 saw the more aggressive E46 M3 which also spawned a convertible. In 2007, the latest V8-engined M3 coupe was launched with buyers only having to wait a year to get their hands on the Convertible, this time round featuring a folding hard top for the very first time.

Convertible buyers tend not to place quite as much store in ultimate handling and roadholding and a little more in styling and sound quality. On the final score, the latest M3 Convertible isn't going to disappoint. In fact, it's one of those cars that will have you scanning the road map for tempting looking tunnels. The aural signature from the V8 engine is like no other road car powerplant, sounding like a sawmill that has just cranked into operation. The cause is the induction system which features an oscillating tube fed by eight lightweight intake funnels. Add a fruity exhaust blare and you have a car that will swivel heads from a long way out.

Buyers get to choose between a six-speed manual gearbox and a seven-speed M DCT Double Clutch Transmission with Drivelogic. Zero to 62mph is dispatched in just 5.1 seconds with the M DCT-equipped car, top speed being electronically limited to 155mph. The M DCT gearbox also features a gradient detection system to prevent roll back on hill starts and a Low Speed Assistant to smooth the power delivery when pulling away gently.

"This V8 M3 Convertible feels a more polished, less raw product than its four and six-cylinder predecessors"

As much as BMW likes to concentrate on the technical details that uphold its claim to building the ultimate driving machine, the company is savvy enough to know that convertible cars such as this sell largely on looks and image so it's crucial that this M3 gets the cosmetics right. Initial signs look promising. The power dome and twin intakes on the aluminium bonnet coupled with the three massive air ducts in the front spoiler give the car real overtaking presence. The folding hard top roof gives the M3 Convertible a purposeful coupe-like profile that looks great with the stock 18-inch alloys and positively evil with the option 19-inch rims.

Other design details include sun-reflective leather, allowing the driver to leave the roof down on hot days without risking a trip to Stoke Mandeville burns unit. The folding roof is a three piece unit, the advantage of which is that you don't need a distended bottom on the car to accommodate the larger sections of a two-piece roof. The downside of stacking three pieces atop each other instead of two in the boot is that when they're folded, there's not a great deal of luggage space left. With the roof in place, you'll get 350 litres of load space. Fold it down and 140 litres is instantly pared from that figure. The operation of the roof takes a so-so 22 seconds. The rear seat backrests can be folded flat to provide additional luggage space.

With a price premium of around £4,000 over the M3 Coupe, the Convertible weighs in at £54,655 on the road if you choose a manual car, the M DCT gearbox tacking another £2,590 onto that price. Genuine rivals are few and far between. With Audi's RS4 Cabriolet being pensioned off and Mercedes' CLK63 AMG convertible costing nigh-on £70,000, BMW has, for the time being at least, a free run at a market that is just waiting for a car like this.

In many ways the product is now better suited than ever to its target market. This V8 M3 feels a more polished, less raw product than its four and six-cylinder predecessors, qualities which suit a convertible car all the more. Where an E30 M3 Convertible seems a bit of a travesty, an argument can certainly be made for the latest M3 to be at its very best with the retractable hard top. Although I doubt I'd be the one making it, there will be no shortage of proponents for this model.

Expect to average less than 20mpg in normal motoring. BMW claims 21.9mpg for the manual car and 23mpg if you specify the M DCT transmission but most owners won't get anywhere near these figures, especially when they've become addicted to the V8 engines metallic yowl at higher revs. You'll be hit hard in the wallet by your insurance broker with a Group 20 classification. Some compensation however, should come with low depreciation, particularly in this model's first couple of years of life when it retains a 'must have' cachet.

BMW's EfficientDynamics programme has helped lower running costs, this M3 featuring Brake Energy Regeneration, using what would have been wasted energy to charge the battery. This in turn reduces alternator drag and improves economy in normal driving conditions. Carbon dioxide emissions of 293g/km still put the M3 Convertible into the top tax banding but when compared to vehicles with similar weight and performance, pay testament to the expertise of BMW's engineers.

Only the most fundamentalist M-car anorak can now get their underwear in a bunch about the latest BMW M3 Convertible. By any logical measure, it's a great car, plain and simple. With a well engineered folding hard top, an absolutely breathtaking engine and a look and feel that now suit a drop top car better than some previous generations, the M3 Convertible more than justifies its own existence.

With 414bhp on tap and a soundtrack like no other production car, BMW has ramped the desirability of the M3 up a couple of notches. Factor in the added safety and security of a hard top roof and the package becomes extremely hard to fault. Our advice would be to spring for the M DCT gearbox and give the 19-inch wheels a miss as they'll compromise ride quality. Whichever options you choose, the M3 Convertible will not fail to impress.