Just got one of those alarms from Ebay. Haven't installed it yet but it is very basic. As far as it draining the battery, most alarms draw such a minimal amount of power you would not have to worry about it killing your battery unless you left it parked for a long time without starting (a month, maybe more). Remember, layered security is the best. Alarm, chained up, aired down tires, boxed in, pistola, whatever else you can think of, the more hurdles the better.