I’m using the Sena 10S, which is pretty much a trimmed down version of the 20S. It will only connect to 4 units for intercom instead of eight like the 20S, and has a slightly less range, 1.4km vs. 2.0kn on the 20S. I liked it because it has a slimmer profile than the others, and really didn’t have a need for the other features. I can connect my Garmin Zumo 660 separate from my phone, but still have both connected at the same time through Bluetooth. The sound is nice and clear, and loud enough to hear over wind and engine noise. I’ve asked friends when talking to them on the phone while riding how the sound quality on their end was, and they’ve always said that they didn’t know I was on a motorcycle till I told them. This is probably the same for the 20S as well. Go here to compare the two.