Neither, I would rather have support for AirTunes than either of these, and as far as I can tell, AirTunes could be supported by a software and shouldn't really require any new hardware. And in means of the radio transmitter, I bought an iPod so I wouldn't have to listen to the radio, and in means of of broadcasting a signal for cars to listen to it, my car has a tape deck which I threw a stereo-mini to tape converter in, which gives much better music quality than a FM transmitter could, and most new cars now (including my parents, I'm 16) have direct stereo-mini inputs.