I've wanted to add a laser jammer to my vehicle for a few years. Now, I'm back to researching and it seems that LI is the one to buy. My V1 has been put to daily use for 10 years, but I'd like a little more protection. My current car is a Toyota Matrix, all black. I'm tempted to get the dual unit, but I just can't shake the memory of being shot from behind from an overpass on my way into Atlanta. Yet, the quads are expensive. Is it possible to buy a 2 unit add-on later?