Structurally, Sharkskin is the same as any number of hardened rubber cases: the iPhone 5 snaps right into the case and is protected on all sides, including the front, thanks to a raised lip. While button coverage is appreciated, we didn’t like that it noticeably decreases the click sensations of the Sleep/Wake and volume controls; you can’t even tell that you’re pressing the former unless you’re looking at the screen. The…