Compare the Renault Megane RS 1.8 Turbo 280 - [2017] vs Seat Leon ST Cupra 300 DSG 4Drive - [2017]. 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 Renault Megane RS 1.8 Turbo 280 or the Seat Leon ST Cupra 300 DSG 4Drive. We'll leave it up to you to decide which is your favourite.