Compare the BMW X7 M50d 3.0 Turbo - [2018] vs Infiniti FX 37 3.7 V6 - [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 BMW X7 M50d 3.0 Turbo or the Infiniti FX 37 3.7 V6. We'll leave it up to you to decide which is your favourite.