Bentley Mulsanne Convertible Concept Bentley previews its Mulsanne Convertible Concept, a 505bhp, twin-turbo V8 rival to the Rolls-Royce Phantom Drophead Bentley used the 2012 Pebble Beach Concours d’Elegance to preview its new Mulsanne Convertible Concept. As the pictures – and it’s fairly self-explanatory name – no doubt tell you, it’s...