Follow-up
I searched for the best price I could find for a Sena SM10 to use with my SMH10-11 BT headset. Found it at
PowerSportParts.net for $115 shipped. Ordered from them and received it in a timely fashion.
Like their BT headsets, the Sena SM10 seem like a good quality product. You can tell that it pairs with the A2DP (stereo) profile as the voice in my headset says "media device connected", not "phone connected." Fidelity is quite good from any source into the "audio" port. It is typical phone quality into the "aux" port, which is fine for an RD.
If I have one complaint it is that its volume, even with the "audio boosting" enabled, is barely adequate with 30 dBA earplugs and helmet speakers. As a direct comparison, the audio volume levels using the same helmet headset are
considerably higher (to the point where I need to reduce the headset volume) when pairing the SMH10 headset directly with my nuvi 765T's A2DP output, or with the zumo 550's headset (mono) output. Those who do not use earplugs, or use in ear monitors (earbuds) will not have this issue.
I will most likely keep this unit for use on the FJR and Vstrom, as it allows me to integrate the RD signal into my BT intercom. I will probably look into getting the SMH10's helmet clamp thingee that allows in ear speakers (earbuds) which should negate the low output levels. I'll continue to use the helmet speaker type standard clamp while on the Pegaso w/ the nuvi 765T. I don't really need an RD on the Pegaso.
Now I just need to get some seat time in with these gadgets to see how their reliability is.