Compare the Mercedes SL Class 450SL V8 R107 - [1975] vs Seat Leon 1.8 20vt Cupra - [2000]. 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 Mercedes SL Class 450SL V8 R107 or the Seat Leon 1.8 20vt Cupra. We'll leave it up to you to decide which is your favourite.