I've tried to use the visor mount for my 9500ix in a couple of rental cars and it doesn't really work. It takes a long time to aquire GPS and will lose GPS contact quite often.
I would think it would position the RD too far up into the window tint? Good idea, but somewhat impractical IMHO.
I should mention, I can acquire a solid lock within 15-20 secs inside my garage as is further explained by the fact that my Sirius is rock solid inside the garage as well. Heck I can go inside my house and get a lock within about as much time too with the RD.
I've wondered about this with convertibles. Would the soft-top on a Jeep interfere, or would it be "clear" as far as satellite signals are concerned? I'm assuming it would not interfere.