I love the idea of that case, its like a wallet and phone case in one. However I can imagine that the credit cards pressing against the screen are going to leave visible marks on your screen. Maybe not scratches or damage, but lines where the plastic/dirt will be rubbing against the glass.
Its a similar problem that happens with some laptops where the keyboard leaves marks on then screen when closed and moved a lot.
Phone: Galaxy Note LTE, Epic 4G, EVO 4G, DROID Incredible, HD2, AT&T Tilt2, AT&T Tilt