These seem to be good quality. I was a little wary of the plastic disk that connects it to the grinder, but it hasn't been an issue. I tested it by using it to basically strop my lawn mower blade after sharpening it and no, I don't think that is worth doing except as a torture test for a buffing wheel. It did a nice job and it was still usable, though a little worse for wear, after about 15 minutes or so of buffing. I made a real effort to overheat it and cause the plastic disk to deform, but it held up well. If you need some wool buffing wheels, these are a good choice.