drove in a van this weekend with it, and allot of my friends have it, the one locally is shatter proof, not bullet proof, you need the thicker hardened glass etc for it to stop a bullet, but i am sure if you layer it on both the inside and outside it will stop most everything - maybe not a bullet, but its still going to slow it down or stop a bat or something from bushing ya head in a carjacking etc..
only prob with it is that it becomes like steel when in an accident, where the glass may break and absorb some collision form you head or something, this will be like hitting your head on a brick wall, but atleast you wont get cuts
