[m110]

[QUOTE=RWebb;4640536]I agree with m110 that mounting can be problematic. I'd love to have a black box built in just below or above the rear view mirror to conceal the V-1.
QUOTE]

I worked on some prototypes for a rear view mirror integrated with a detector. One had the mirror a touch closer to the driver and a notch cut for the rear sensor with the unit ahead of the mirror. Another had the unit sitting under the mirror. There is company that makes a mount that suspends the V1 from the mirror nicely. Above the mirror location seems to have a problem with the slope of the roofline obscuring the rearward view (although I don't know if this makes a difference in reality).
I abandoned all these because I drove around with two valentines for a few months. One in the optimal location of front and center just below the mirror and one in various locations like the back window suspended from the third brake light. I couldn't tell a difference in detection capability. It obscures rearward vision a little but it's ok.
I also drove with a V1 and Escort side by side....sometimes both on, sometimes one or the other. There probably is some interference from having both going but I liked the V1 better. They were pretty close. The extra mounting V1 options sealed it for me. I believe escort has more mounting options now as well.