Just bought a 2009 Z4 E89 sDrive 23i Black with ivory leather a week ago and just beginning to get to grips with all the computer stuff. I am very impressed with how well it has stood the test of time. On the test drive I thought it drove ok with the new Falken run flats but now I have put a few miles on it I will HAVE to put a set of conventional tyres on, so will be putting a few posts on about things. Looking forward to your answers. Cheers