Too bad we couldn't put a PEP in our auto's....
Thief breaks into car, thief gets blasted with ray beam, thief incapacitated and passed out in car,lol.
My father and uncle used to have it set up where if people touched the car, ZAP!!!!!!!!!!!!!!!! can't do that anymore.
Anyway, my suggestion is to get one of the cheaper air horns and put it inside the car, hidden, and this way no one will want to go inside when the alarm goes off. you could also hook up a 12 volt smoke machine and strobes to add to it. Anything to keep a thief away.
I would rather them break the windows pissed off than to steal the whole car.