My only criticism of this die grinder is that it doesn't rotate in the air chuck housing. It's okay, I'm just one of those people who obsess over things I don't understand. And I can't understand why they put this grinder in a case that you can't use if you don't remove the air cartridge every time you're done with it! In addition, this small tool is very handy and can be used for a variety of jobs. Personally, I have an air compressor that does 8.8 cfm at 40 psi and 6.7 at 90 psi, so this thing works horribly. It was a bit pricey considering I've seen them (another brand) for only $15 without any accessories, but I would definitely buy them again.