The Bentley Flying Spur is over seven feet wide. Wider, in fact, than a Hummer H1. Just twenty inches narrower than a Smart car is long. Ironically for a marque so closely associated with Britain, that makes the Flying Spur singularly unsuited for a great many British roads. And, with a price tag easily ten times that of the Smart - and dwarfing even the cost of a full tank of gas for the Humvee - it's not something you want to scrape along one of the ancient stone walls you suddenly notice the UK has in abundance when you're driving a borrowed behemoth.