Spacious, innovative and safe, the compact models of the Mercedes A and B-Class score with their high practicality, and have found favour with more than 2.5 million customers as a result. An extraordinary one-off example has now been built at the Rastatt plant, and shows the B-Class in a completely new light: a B55 with a V8 engine and rear-wheel drive.The idea came from the Rastatt plant