I had a huge scratch from who knows where on the glass screen of my ipod touch. After that, I'm erring on the side of caution, especially as the vzw protector is all but invisible when put on right.
You didn't hear this from me, but if you stick a paperclip inside your phone charger port and give it a nice couple jabs the Verizon store will replace your Droid on the spot, no questions asked on how it happened.
Motorola has an extensive history of failing charger ports, Droid will probably be no different.
If by some amazing occurrence I scratch the glass I'll be getting a paperclip out of my desk drawer.