Funny story:
So when my wife got an iPod Touch, I put a ZAGG Invisible Shield on it. I told her the Invisible Shield was scratch proof, and decided to show her with my keys. I took the iPod Touch and went to town for a couple seconds on the protected screen. IT SCRATCHED! Luckily, it was a small one at the bottom, but my wife looked at me like I was retarded, shook her head, and took the iPod back. LOL
Just because you see people on the websites do it doesn't mean you have to witness it first hand.