My Genius Bar took my rMBP to replace the screen (image retention) and to replace the case (was creaking and I convinced the guy it was bad for the case to tap the battery). However, I'm just wondering if Apple guarantees their work. What if I get my laptop back and it still has image retention problems, or the case still creaks? Will Apple fix it again? Just would like a little peace of mind, and a Google search didn't turn anything up for me.