Oka let's get to the bottom regarding apple iPhone bumper case (scratches)

Now we have all (most) heard rumours that the iPhone 4 bumper case scratches the iPhone or at least that's what we're led on to believe well after debating if £26 was worth having a rubber band around my phone I took the plunge thinking metal can't scratch metal surely! I put it on straight forward, although I did notice apple still felt the need to put instructions on the back though, that was quite amusing. Anyways after removing after a few days or so havnt taking it out and about etc I can happily say no such thing. But I believe the trouble occurs if debris gets in between the case and phone and of course being there's a bit of giv on the case that results in friction that results in scratches. Is it worth the money/trouble we'll that depends other than having no real purpose it's pretty pointless to be honest! But you might like the look I'm still asking my self the same question. Now where's that receipt.