I love the functionality of this case! It works perfectly. I keep my work key (a digital proximity card which is the size of a credit card) in this case, so all I have to do to get into the office is hold my phone up to the card reader. It's also really nice to be able to go shopping or go to a concert and only need my phone cause my credit card and license are stored in my phone case.
The only thing I don't like about the case is there isn't much silicone on the case, so it slips out of my hand too easily. I used to have the Otterbox Defender case and I prefer the grippiness of the slicone case. I understand that this case needs to be structurally strong to hold cards and not destroy them, but it would have been great if they found a way to put more silicone on the edges of the case. It seems durable, but with the lack of silicone, it doesn't have much bounce, so that can't be good.
Anyway, it's still worth the convenience of this case.