I just bought an "Incase" case for my phone. Got it at Best Buy. Not too thick but not too thin. It's hard white plastic with a black rubber bumper around the sides/corners. Grip is good. It also has a detachable bottom for "easy docking." The inside of the back has a cushion on it so it doesn't scratch the back of the phone.
The cons are that the buttons (side volume and top lock) are a little difficult to use. I also did buy a screen protector with it, but the protector was a piece of junk. They gave me a wipe to wipe the screen with, but it did nothing but produce massive amounts of lint so it was useless. Then the protector itself got scratched just by me pressing down to squeeze the bubbles out. Finally, the tab that they give you to align the protector without putting fingerprints all over it was GLUED to the protector so bad that I couldn't get it off without it leaving residue all over. I quickly threw it out.
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