I have a chatterbox that works great up to about 50 m.p.h. me and my wife talk bike to bike. Apparently, and I haven't tried it yet, but you are able to plug both a cell phone and an mp3 player into it. They say if you are listening to music and the phone rings that the music will mute and allow you to answer the phone. They are a little pricey, but being that I was teaching my wife to ride, it was worth the money to me. I dropped about $280 for each unit. Yeah-$560 for the set.