Audio books, what a great idea when doing long distances.
I listen to audiobooks frequently and plan to set my scoot up for this purpose over the winter, probably with a 20S system and iPhone combination. I recognize I'm in the minority, but I wouldn't spend a lot of cash to upgrade the entertainment system - amp/speakers, etc. I've spent way too much on various other mods though and doubt that will stop. The 20S headset speakers are supposedly far superior to earlier versions, so piping the audio into my helmet works okay for me.
I have been looking at this idea also, but am concerned about the battery life
There are multiple users reviews on line dep47, but the jury is out on battery life. One review indicated 13 hours 'talk time' on a charge, but it hadn't been tested towards longevity. The headset can be charged on the fly as you ride if doing a long day. This would entail a wire to the headset but may be doable.