Compare the Audi A3 2.0T FSI S-Line - [2005] vs Seat Leon SC 2.0 TDI FR - [2013]. 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 Audi A3 2.0T FSI S-Line or the Seat Leon SC 2.0 TDI FR. We'll leave it up to you to decide which is your favourite.