Hey Guys, I'm new here and new to the X3s. We just got my wife one a couple weeks ago. I may be able to recommend a good tire though. Continental has just released the new Continental Extreme Contact and Extreme Contact DWS. We just put a set on an '09 Mitubishi Lancer GTS. They are a really quiet and smooth riding tire. I mention it here because some have mentioned the sidewall being a little soft (lancer forums and tirerack.com) which is just want you need to soak up bumps. Our Mitsu rides better now and still handles great (225/45/zr18).

FastLane
'06 x3 31k
'09 Lancer GTS
'88 Toyota pickup 22re 4x4, 5 spd. 58K mi.