Had one on my 99 Dodge 4x4. I loved it. Before they became popular (at least in AZ) it was a kick to see peoples reaction. I had a VIPER Alarm with the Car start and Off, With window roll up and down, shock senser etc.. People would walk by and you could start the car to freak them out. As they got closer to the window I would roll it down and they would really freak out but the trick brought them closer. Then as they got close to the window I would roll it back up and turn the car off.
It was a good Candid Camera trick. The range was about 150 feet for mine.

It was handy. Before getting into the vehicle I would turn the car on and let the A/C run about 5 minutes before I left. Same thing for the winter with the heater. This way I wouldn't sweat or freeze like crazy. It was actually more handy when I go hunting as I would have the Vehicles interior warm before getting out of my sleeping bag. The Alarm is still active so if someone gets in there is a sequence of events you have to do before taking off even though you put in the key to turn the ignition after you turn the alarm off.

The down turn was the extra fuel you will burn having it running but back then it was a nice COOL option to have and the fuel prices were not as bad.

I paid I think about $450 back then.