The PS switch went bad on my 98 Z3. I had to get the numbers off my old switch to get the correct one, as their seemed to be some problems looking it up in the parts dept. of my 2 fairly local BMW dealers. After taking in the old switch, it only took 3 days to get a replacement. My cost was about $120, I don't remember exactly. Putting it in is fairly straight forward, but you do need to take the seat out. I did not take the seat belt out, but just turned the seat over to access the bottom. Not the easiest job in the world, but got it done.