The BMW i8 is one of the most distinctive cars you can buy... ...and the i8 Roadster takes it to the next level. Many will buy one for its outrageous looks alone... Many will buy one for its outrageous looks alone... Many see the i8 Roadster as a rival to the Porsche 911 cabriolet and Audi R8 Spyder With a 0-62mph time of 4.4 seconds, it can certainly compete on performance However, thanks to its plug-in hybrid power system, the i8 has another trick up its sleeve A lithium-ion battery pack has enough capacity for a 33-mile range in electric-only mode... ...which offers a top speed of 75mph This means that many will find the daily commute possible without the petrol engine ever starting. It's this technology that allows BMW to claim fuel economy of 134.5mpg Yet, when the petrol engine is engaged, the i8 Roadster's top speed is an electronically limited 155mph The electric motor drives the front wheels, while the petrol engine turns those at the rear. That adds up to four-wheel drive, which means tenacious traction and grip on a twisty road. Some may find the i8's slightly arcade-game feel a little unnatural... ...but others will find it an exhilarating high-tech marvel.