Compare the Lamborghini Diablo GTR 6.0L V12 - [2001] vs Mercedes SL Class 65 AMG V12 Black Series R230 - [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 Lamborghini Diablo GTR 6.0L V12 or the Mercedes SL Class 65 AMG V12 Black Series R230. We'll leave it up to you to decide which is your favourite.