Works for one car but not the others...
Ok, so I've tried this gizmo in both of my cars. In my Ford Mustang it works only partially. It picks up a lot of static and interference from everything including acceleration of the vehicle. Now in my Audi TT Roadster it works really well with almost no interference. However, if another car is using a CD player, IPod, etc with an FM modulator, THEIR music completely overrides your music. For a hardcore music listener, find something better. I will admit that the 2 AA batteries seem to last. That is a positive note.