Don't know if it's been discussed yet, but another element to consider for some people ( i.e: me) is that a communications system have coupling capability with a CB radio. I have the Sena SMH10 which, as I see others have mentioned, works very well for BT connectivity to my Zumo and iPhone. Then they came out with the SR10, which acts as a BT hub for all the communications assessories, including the CB. So it prioritizes and senses whichever signal is coming in and relays that to the helmet speakers. Pretty cool!