Compare the Jaguar XJ R 4.2 V8 Supercharged - [2003] vs Bentley Continental Flying Spur Speed 6.0 W12 - [2008]. Find out which car is the fastest, most powerful, lightest or has the biggest engine in our top trumps style comparison page. Find out which car has the highest top speed or is the fastest accelerating, is it the Jaguar XJ R 4.2 V8 Supercharged or the Bentley Continental Flying Spur Speed 6.0 W12. We'll leave it up to you to decide which is your favourite.