i have this antenna in my mustang for like 2 years, it is currently connected to a sirius sportster. i tried this antenna, and an outside one, and the reception is almost identical. this is the one i am going to be using for my avic z1 sirius tuner. it is a nissan SIGMA antenna, cost about $70, and no ugly antenna outside the car!

it as barely noticeable mounted above my gentex mirror

It's the piece of wire there?

no it is the black kind of triangle thing stuck to the inside of the windshield.