I just bought one of these today and tried it on Auggie. Wow. Okay, I thought I was doing a really good job of getting all the dead hair out by brushing him everyday. Apparently not.
I brushed my sister's Kota, and he didn't seem to like it - I think it was pulling at his fur way too much (different coat texture.) Happy was fine with it though, and holy crap did the fur go everywhere.
I have to admit... I was curious, so I... tried it on myself. X3 It didn't rip out or cut my hair at all, but it did kinda pull a bit. I think it depends on the dog and their fur texture, if they can handle it or not.