A good friend proudly took delivery of a new 335 cabrio(UK) in nov `07 and has now got what I think is a serious problem. It eats rear tyres at the rate of 4k a set. At the last service(22k) she was told that the tracking was spot on but both rear wheels were broken. It turns out they are cracked from the rim edge to the hub but with no evidence of kerbing.BMW say its hit a pot-hole, huh? With both rear wheels, a hell of a hole. It smells of a defect of some sort or another,there is no evidence of grounding either.Any other folks with similar stories??