I have traveled in groups a few times and listened only. I don't have a mic and just listen to the leader and the tail guy converse through the bike's sound system.
For phone, music, navigation, converse with passenger, and talk to other riders I use Bluetooth with the speakers added to my helmet. Completely wireless. I use the UClear brand in a modular helmet (wife has full face).
UClear does not have mic to add to the face of your helmet or a boom mic as the mic is built into the speakers. Visit their website to see the technology behind this.