To be honest, I found that my Motorola Finiti bluetooth earpiece microsUSB didn't have any barbs on it. So that was what I used... no probs with my N900 while I had it.

But I had mine for just... like 7 months in total - give or take, I didn't really use it much in the end.

Good luck with all of it man. You'll find the N900 to be a decent phone, pretty capable actually.