My next Amazon shipment is going to have a couple of those window breaker + seatbelt cutter combos
The problem with the hammer style is you might be injured or pinned in a position where you can't develop much force. Also hit the corner of the window, NOT the center; I've bounced a sledgehammer in class off the center of regular window glass, it's amazing.
The woman who died in the Tesla must have had a horrific death, that shit is utterly terrifying.