The good thing about the viper is when it's set it,it will let anybody who walks within five feet of the vehicle that it's protected by viper.once the door is tried to be opened the lights start flashing a siren goes off as well as the horn,and in some instances the ignition is disabled.

 

I like the Viper but sometimes they are set a little too sensitive. I have trouble walking and sometimes I have to touch a parked vehicle to stableize myself. Can be rather embarresing and hard to explain.

Also nothing like a customer fergitting it on and you go to raise the hood to work on it and all hell breaks loose. Especially if the customer has allready gone.

 

I'll add another vote for the Ravelco. I've had it in my truck for about 5 or 6 years, and it's done it's job more than once.