I work for Cellairis. Leader in accessories. And even though G2X comes with a screen protector on the phone, it's not exactly a good quality one. I placed our own screen protector, which we call "HD screen protector", and the quality is totally different.
I mean, when i pealed of the old one, it felt same like any other plastic which comes on a new phone, but just a tad bit better quality, hence it looks like screen protector. I recommend to get a "real" screen protector as it helps if your screen gets in contact with your car keys when kept in pocket, the little thickness would keep your screen away from getting scratched.