I installed my AFE about a month ago. It was an easy install - 45 minutes all buttoned up. The difference is a little bit better sound whenyou get on it, lol......listen very hard. Beyond that it is not just psychological....when in a passing gear and you get on the gas......it definitely opens up for you.
Here is the thing - the solution looks cool, but performance wisew it does not turn you X into a 1988 Mustang GT.
Now when I added my Supersprint exhaust, in conjunction with that....it is an awesome set up. It all boils down to opinion, choice and tatse.
Now go install the damn thing!
PS - Read my thread about the blue filter turning white....
http://www.xoutpost.com/x5-e53-forum/...?highlight=afe
RR