Very few screen protectors look good once install. Almost all of them diminish the clarity of the screen to some extent. I don't buy these nice touchscreen gadgets to keep them nice for someone else to use months or years later, I buy them for MYSELF, and I intend to have the nicest view of them I can have. That means no cheap plastic covering the display.
I'm with u I have had my i4 since launch no protector and still no scratches
I would guarantee you that you have small scratches on yor screen