I was excited at first because it has a good grip, but it started to become annoying because to place it, you essentially stick it to the inside of your case, and since most cases are quite thin, it adds bulk and ruins the fit of the case on the phone. Also, in one of my cases, I didn't have a "square" opening for the cameras (like in the photo), but small round openings, and I passed it through the bottom opening, resulting in the camera capturing a dark area at the bottom in the photos (it was in macro mode which I don't use often, so I didn't mind)

It has good grip, but it adds volume to the inside of the case, resulting in the case not fitting well on the phone. Nevertheless, it is stable and convenient for one-handed grip.