I've had an Otterbox defender on my iPhone from day 1. I've dropped it many times and have not had a single problem with my phone. Otterbox even replaced the silicone outer shell for free after it stretched out. As for Lifeproof I have not seen or experienced their brand.
I have an Otterbox for my iPhone and I've had it for quite some time and it doesn't even have a scratch on it so I would personally try Otterbox. But just saying I have never even heard of a "Life Proof " case. Hope I could help!! :)
The only negative thing I've seen about otter box is if you carry your phone in a dirty environment dirt gets trapped between the cover and the screen scratching the screen on the phone. Use a screen saver under the otter box cover. I'm not familiar with the other brand though.