I just bought two Otterbox Defender cases for the 4S at an AT&T store. I am thinking about removing the built-in screen protector and using a Power Support Crystal screen protector instead. Has anyone done this? I have not received my 4S yet. Would the screen protector fit well? Thanks for any help. Btw, I want to do this because I have read comments stating that the touch sensitivity goes down with the built-in screen protector.