We been using a Blueant Interfone (interphone?) for a few years, now the newest model. The daVinci requires a bit more stoker cooperation when shifting and my high frequency hearing is not the best. Also, we find it convenient to be able to answer our phones when necessary. Yeah, it looks pretty geeky, but we are riding a daVinci.

I actually use the headset on my single if I'm expecting an important business call.