Yep... I used the Motocom interface box which connects to a Motorola Talkabout for the actual communication. I've also tried a chatterbox. The motocom/talkabout setup was unusable at anything over 20 miles an hour. It was garbled and had much static, regardlesss of the distance. The chatterbox was OK but still not very clear or loud.
We've installed a J&M CB unit on my wife's Street Bob so she can talk to me on my USE3. I frequently ride with her, a Road King, and a Sportster all using the same unit. It allows us to all communicate with each other, plus we get the benefit of them being able to talk to the wingers and Ultras when we ride with them.
It's expensive, but easy to install and includes a 1/8" input for MP3 etc. Also has weather band on it. My wife loves hers and we can communicate clearly at any speed. Well, as well as any husband and wife can communicate. You can find more info on the unit at:
www.jmcorp.comHope that helps.
J-Carr