I had a 97 325i, with the M package...I loved that car. Favorite car I've ever owned; fast, great pick-up, great transmition, looked great (Hellrot red).
Currently I have a 97 M3 sedan, which is a lot of fun, but I still liked my 325i more (fewer problems). I wish it wasn't stuck back in Calgary

I love them just because they're a lot of fun to drive, and look great (especially the E36s). The mechanical stuff is obviously a little more complicated, and expensive for parts though.
My parents just bought a 2011 135i last week...I'm excited to get back to Calgary this summer and rip around in it for a few days...if only they would have gone for the 1M instead