I have the window mount, the type that sticks on the outside and has a piece that sticks on the inside.
My out side piece, antenna, fell off twice. The secont time I was out of town and it rained. So it sat in the water in the bed of my truck for a while. I had to buy a new one but Circuit City installed the second one at no labor charge.
It's getting colder now so it will be interesting to see how this one does wneh it starts icing up.
Hoped this helped.
Craig