I want to get an alarm but dont know which one to get. I'm debating between the compustar 2wss-a and the viper 791xv. The compustar has a way better range, but some people tell me that compustar's have a lot of problems. Does anyone have any input? On eBay I've seen the 791xv for $185 and the 2wss-a for $205, so not much of a difference.