There just isn't a point. No one reacts to car alarms. Driveaway protection in your key makes it hard to steal anyway. The extra measure of protection I would install instead is the so called fuel cutoff system. It's very popular in Europe. I have to look into it if it is available here. What it does is basically this: let's say someone was able to start your car with something else then your coded key or with your stolen key but did not know that there is a small hidden switch in your car which you have to press after you start it, what will happen if you don't is the fuel will be automatically cut off after a minute or so and thus immobilize the car. Sometimes it is not even a switch but a small piece of metal which you have to touch with another small piece of metal you carry on your key chain to "unlock" the system. But then again, car theft is not such a big issue here unlike in Europe. Car vandalism is more so... and idiots in big a** SUVs backing up right on you (just happened to a friend of mine and his E36, the b**ch was on a cell phone...)