I installed a Viper alarm on my nv 2500. It's the alarm I put in all my previous service trucks. This time, I piggybacked a Smartstart to it. It works awesome and I've started my van from inside malls, hospitals even three blocks away. The neat thing is that I signed up for their GPS tracking for $100 for a year. I can set geofences, track my vehicle in real time, set speed limit alerts, activate panic mode and it will alert me if the van is moved from where I set the geofence.