I don't have one nor do I know anyone who has used one. However, one of my Beagle Bay members ordered one recently - don't know if she's gotten it yet or if she's tried it. But if she does, will let you know. I'm withholding judgment - too many of these things are well-advertised, but I'm a little too cynical to believe everything I read or see on tv. I think I'd still need someone to hold mine - I can't hold and clip.
I'm using it! It is wonderful, although Charlie is still afraid of it. Because it vibrates, and makes noises. I hold him cuddle him to my chest, praising him and petting him. While my daughter file his nails with it. It does not hurt him at all, just making sure you won't file too close to the nerves. It files slowly down, you and your beagle must have patience. I think I paid more than that!