I've been through several bags of FVM wheels by now. My experience with the older bags (the ones with the grey paper labels) was similar to others: a few percent failure rate. Some could be easily re-assembled, but others just had a bum insulator which required replacement. However, my experience with the newer runs (white cardboard labels) has been much better: closer to 0% failure rate, though some do have a slight wobble. Maybe I have just been lucky lately, but I think the quality control has improved.