Just finished hardwiring my Valentine1. I chose to tap into the power wire for the rear view mirror so I don't have to turn the V1 off when I don't need it.
I couldn't bring myself to use a vampire splice so I took the factory connector apart and soldered a short wire to the side of the terminal.
So far the suction cups are holding up ok on the windshield in this position. If they have a problem I'll try some thick clear vinyl and use it to "dull" the texture and hopefully give the suction cups a better seal. In this picture the mirror is in the highest position it will go.
And here is a view from outside the car showing that the front radar sensor isn't impeded.
I routed the V1 power wire in the same channel as the wiring for the mirror. Since there doesn't seem to be a good place for the V1 junction box I just wrapped it in sticky foam tape that came with the bluetooth kit so it doesn't rattle up above the headliner.
Steve