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Be careful when installing it due to the liquid spray. Some overspray or seepage could EASILY get into the docking or earphone ports while installing and set off your water damage sensor (especially for the docking port) voiding your warranty.

I never spray stuff directly onto the screen for that exact reason. I just spray into a cloth and then wipe the screen with it.
 
I've been debating this and my final verdict(for today at least) is I'm going to keep my 3GS in the incase that I got for it and leave the screen uncovered.

I sold my 2G iphone that I had a few days shy of 2 years on Friday and it's never been in a case. The bezel and back were pretty bad but the screen was literally brand new condition. Took one of my car microfiber cloths and went over screen to remove all fingerprints and such. Was shocked.

My brother and father use the invisibleshields on their PRE's. They are nice. Although I can only recall dropping phone once in a two year period if I'm going to use protection would rather have something to help absort drop then stop scratches.
 
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