I think the driving difficulties are related to the CDV (clutch delay valve) on the manual transmissions. It's supposed to protect the drive line, but in doing so wears the clutch faster. From what I read it is an easy mod to do. I don't have a 540, but I have been looking at them also (I want the 540/6 speed). Here is some info on what breaks, and some links to other websites like it. http://www.540i6.com