Compare the Jaguar XJ 3.0D V6 600 LWB - [2009] vs Alfa-Romeo 159 3.2 V6 Q4 - [2005]. 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 3.0D V6 600 LWB or the Alfa-Romeo 159 3.2 V6 Q4. We'll leave it up to you to decide which is your favourite.