I use a Sena and S-Plug ear buds and have always used my Zumo for music. The App will allow that to be used via the bike so I have 2 options. I had a couple goldwings and they all came with the speakers/radio/etc as part of the basic package but I found that I never used it because it just wasn't as good as helmet speakers or ear buds.I've held off on the radio so far, but I might get that done too. I think this same parts guy has a parts list for the radio retrofit. I'll try to get that too.
However, at the price point we pay for these bikes, we should get that whether we use it or not.