This is almost perfect. The way to make it perfect would be if the stopper/guide would stay where you put it, but it doesn't, at least on the one I have. Sometimes have to slide it back in place before you can actually complete the clip. That's the caveat mentioned in the review title.
That aside, it cuts cleanly, easily and quietly. I've got a little Ratchi (about 10 pounds) that has very long 'fingers' with nails that grow so fast you can watch them do it. With the little guard/guide in place, you don't cut so much that you hit quick, so your puppy is happy about that. With smaller bits removed more frequently, the process becomes familiar to your pet and they don't fight you about it.
Now I can cut her nails with very little fussing and no worries about hurting her. These are very nice and the price is quite reasonable. Saves me from spending $25 and getting her all riled up over going in the car to the vet for that, so we both win!