Compare the Koenigsegg One 1 5.1 V8 Twin Turbo - [2014] vs Koenigsegg Agera 5L V8 - [2011]. 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 Koenigsegg One 1 5.1 V8 Twin Turbo or the Koenigsegg Agera 5L V8. We'll leave it up to you to decide which is your favourite.