I had Otter Box when I had my iPhone. Very bulky. When my wife and I decided to change carriers to save some $ I got a Galaxy S III and a T-Mobile D30 slip on case.
I work on a concrete shop floor 5 days a week + detailing and my phone has yet to have any problem after being dropped.
Yeah it's T-Mobile but it's cheap and working on the printers I do the electro mag field is so strong that it garbles just about any cell phone call quality.