I had an Alpine Nav Unit. They smashed my passenger window and grabbed the deck from the outside. $6000 in damage!!!!!!!!!!! The factory alarm does not work if you don't open the door. The @#$@holes know that when they broke in. Now I'm trying to decide if I should go stock or upgrade to a better alarm with glass breakage and motion sensors.
Some pics
8.) This unit is $184 or so at Best Buy,