Does anyone know if the viper alarm's (particularly the one with the responder) sensors are good enough to detect some ******* keying your car? I'm considering the alarm for more than that reason, but it'd be nice if it would. If not, know of any alarm that would?

 

The only way an alarm is going to go off on a keying is with a promiximity sensor which won't stop them anyway since the act of keying takes only a few seconds. I suppose they sould set off the shock sensor, but it'd have to be pretty sensitive, and it wouldn't stop them either.

There really is no way to stop keying or tire slashing unless you park in a garage...

I can see my car from where I sit at work which has stopped two attempted break-ins, but anyone could walk past it and key it.

 

http://auto.howstuffworks.com/car-alarm.htm