For the price, I can't complain. Like I've read elsewhere, the spanner nut that holds the tool head in wanted to back out after just a couple of minute's use. My fix was to stake the edges of the collet housing over on the nut to prevent it from backing out.

Also, the angle gearbox needed lube when I got it. I pumped grease into the flush fitting then ran the tool with a rag around the end to catch the excess grease. After these mods, the grinder works fine. For $19.99 (what I paid on sale), I don't regret the purchase.