I'm very close to getting a GPS for the vehicle. It has two good things in that it can monitor speed, and location. In today's society, I think it is fast becoming a must to know where your own or your child's vehicle is at all times. You can also get it to disable the vehicle, and entry level systems are in the $500 price range plus a few bucks a month for monitoring.
If you have a 1970 Pinto you're probably safe from carjacking, but an SUV or any Honda or sports car and you could be a victim. To be able to go on the internet or call the law enforcement people and track your stolen ride is a pretty reasonabe investment.
Some of the systems let you establish zones. ie you live in NJ and you tell your child to stay out of NYC. You set a zone around NYC and if the vehicle crosses into that zone it can page you. We could have used that to keep someone out of crack town. Ya gotta do whatever you can sometimes.
Carl Navarro