I'm seeing disappointed users finding the new Sena 30K won't pair with earlier versions. We are really happy with our 20S units. Seems a bad move by Sena if it's the case.

Huh, I hadn't heard about that.

I hadn't looked at it yet, but over at Revzilla they have one of their video reviews:

Reconnects with lost riders when they are back in range?  We often get out of range from one another and lose contact. The units reconnect but only when you're very close.

Interesting--the specs claim that you can speak with both newer and older Sena headsets--via their 2.4 ghz mesh technology for the newer ones and via bluetooth for the older ones.

Hopefully any bugs being discovered by users will be fixable via firmware updates...

It seems that the 30K is intended to be backwards compatible with the 20S protocol (though you'll be limited to the features of the oldest unit in your intercom group). If there is indeed a problem with pairing a 30K and 20S, it's probably a bug that Sena will fix with an upcoming firmware update.

One of the positive things about Sena is that they do regularly publish firmware updates to correct problems and add features to their existing products.