Tested my second case
I have a 3Gs that has been wrapped in the Mophie air and survived several drops onto hard industrial carpet.
This time it was in my newer Otterbox Impact Gel case and dropped while walking in a lobby of hotel. Landed face down on tile floor and planted rather solidly. I was shocked that it landed without issue. The case certainly did it's job of protecting the screen and absorbing the impact, even from a face down fall from waist high.