I love the ResQMe, I have several. I had to prove it to myself, I was a skeptic, but it punches out side window glass if you hit near the edge, and cuts belt no problem. The one I have in my truck is mounted just in front of the center globe/light. I pulled the headliner out, punched a couple holes in it, and stuck a grommet in each hole. That way I can loop the keyring through those holes, and it is easily accessible from anywhere in the truck, which is what truly counts in the times you need it.
"I would rather live 40 years of excitement and fun and exhilarating and just WOOOO, full volume, then 80 years of la di di di da... you know... boring. Why not get out there and live it?!"