The failures affect less than .1% of those models.
We have a 01 convert, got the letter, climbed around under there and find nothing. There's a good video on the bimmer forum for anyone that want's to inspect themselves, see what it's all about.
BTW, trying to convince the wifey to trade her 325Cic for a boxter, no luck. We went and drove a '05 's' model with a stick and it scared the crap out of her. OTOH, I loved it. Was the closest thing to my street bike I've found, and you can sit side by side, no helmet required.
Maybe I'll get one for myself and let her keep her old sled. Really, the bimmer has been fantastic. Bought as a cpo with 30k, now has 85k, just routine maint. Not really very hi-performance though, especially not compared to a box-s.
I would also consider a 1-35 coupe, the one with the big motor, but have not compared one side by side with a box. Definitely easier to work on/maintain. That's bugging me about the porsches.