Review (4/5): Great if you want uniform designs on both hands
Grooves are of a good depth to trap polish into the designs.
I like that there are so many options to choose from, and that each disk came covered with a plastic film to keep them from scuffs.
I recommend slightly thick polish that is not so transparent so the designs show up on your nails. Do experiment with the polish you've got to see what combinations look best. Also, to minimize scratches, try using an old gift/credit card instead of the metal scraper that comes with most stamp kits.
What's great about using these is that it makes having patterns on your nails easier to do yourself, especially if you're the kind of person that does better on one hand than the other.
The disks are borderline sharp, being so thin as they are. Definitely handle with care. Do not kung-fu grip these unless you plan on stamping with your own blood.