Compare the Radical RXC Turbo 500 3.5 V6 - [2015] vs Audi A3 S3 2.0 Turbo S-Tronic Sportback - [2012]. 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 Radical RXC Turbo 500 3.5 V6 or the Audi A3 S3 2.0 Turbo S-Tronic Sportback. We'll leave it up to you to decide which is your favourite.