I know this is subjective, but do you guys use a back screen protector for your 5/5S? The Wifey and I are OCD about our phones. Never really played w/ the 5/5S she was so happy when she ordered a 5S this AM to replace her 4S. She wanted me to pick up screen protectors asap. We have always used Power Support, so when shopping around I see they make back screen protectors. My understanding of the 5/5S is the back is not all glass like the 4S, but aluminum and glass. Do the dry screen protectors work for the back? Is one needed for the back?