Owned mine since August. No scratches.
SGP Ultra on front, absolutely no degradation of Retina display quality. PhantomSkinz matte on back.
Only recently I've started to keep a case on it.. I swap between a Magpul case and a CAZE Thinedge bumper. Reason? I finally got a dockextender for the bulky ipod connector in my bmw. No longer do I have to remove the case to plug in my iPhone!
It goes wherever it fits: backpack pocket, lab coat pocket, jacket pocket, jeans back pocket, suit interior pocket, cupholder, etc.