I have done this very same thing with my i5 in an otter box defender with the same result. I have also dropped my phone from 50 ft in the air (I work in very high places) it bounced several times and landed in a creek. Both times I took my defender case off and wiped my phone done and put case back on. Everything works still. My case just has scratches on it. Can your life proof fall 50 ft with out breaking ? Doubtful my roommate has a LP and it broke when he tripped and fell on it. My option life proof is extremely over rated. I'm waiting for the taktik case.
My wife has an Otterbox Defender and, sorry, but her phone would not survive a 50ft drop, let alone water exposure (other than a quick misting, maybe a splash). It's one of the worst cases I've ever purchased, given that the silicone comes off easily and tears. Not worth buying. The Commuter? Probably a better case, given that it's not as expensive and doesn't seem to be as breakable.
As to those who purchased the LifeProof iPhone 5 case and are disappointed: I completely understand from the point of view of going from a standard case (Otterbox, SwitchEasy, Griffin, etc.) to it. My personal view is that this case is built to be impervious to the elements and the drawbacks (muffled tones, screen protector gap) are outweighed by the fact that I do not have to worry about the phone at all. Once I came to understand that the plastic protector has to withstand the water pressure of a 6ft submersion, I understood the reason for the gap and the flexibility of the less-than-stellar plastic screen. Same with the rubber material covering the speakers.
I feel like LifeProof failed in their marketing of this product by not being forthcoming about its usability versus the standard cases on the market. Did they build hype? Yes, but that hype has obviously faded now that the product has been released to the public. Is it the best everyday case? No, not by a long-shot. Is it one of the only cases that is waterproof? Yes. Is it the only waterproof case (other than the Incipio Atlas, which might be vaporware) that is small enough to be used every day and be put in a pocket? Yes.
Also, even though I paid full price for my LifeProof, there appears to be a wholesaler who has them for $55 + $7 shipping, but I can't speak to their validity as a vendor:
LifeProof Protective Case for iPhone 5/4/4s | WHOLESALE FACTORY