I have a full IS (front and back) on my iP4, and have gone thru many cases
Griffin Reveal: No, doesn't not work. The back plastic shield sticks to the IS and when you try to take it out of the case, the IS comes right off, completely screwing it up
Griffin Reveal Etch: works ok, for the most part.
Belkin Grip Vue: works fine with the IS (started yellowing, so I returned it)
Best Buy rocketfish tpu case (with back design): might start to peel the IS on the front
Belkin Vue Elipse: the one i'm using now (black/clear): works great