Buffing compound is so cheap for the time it lasts, that economy reaches diminishing returns. Quality ,however, is a different thing. A cheap buffing compound from China (HF) could be of low quality , have lots of filler, and poor grit accuracy (and probably contains lead). I would get it from TKS, Jantz, K&G,an industrial supplier,etc. A one pound bar will last a long time.
Stacy