Compare the BMW 4 Series M4 Convertible F83 - [2017] vs Subaru Impreza WRX STI V4 - Classic JDM - [1997]. 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 BMW 4 Series M4 Convertible F83 or the Subaru Impreza WRX STI V4 - Classic JDM. We'll leave it up to you to decide which is your favourite.