I have the 20s and really like it.
Here are my thoughts.
If you get one with a built in camera you can't use it in other areas on the bike or use it doing something not bike related.
The 20s last a really long time per charge. I can go all day with no problems.
The 20s has good range as I have tested it at about a mile (straight line) and no problems.
The 20s has a handlebar remote (I have one) and it
only works with the 20s. It is really nice to be able to turn up or down the volume
without having to reach up to the helmet. It does most of the features of the jog dial so I rarely have to reach up to the helmet.
The 20s has built in FM too - not sure about the other unit.
The 20s can blue tooth to 2 devices (maybe 3 if you count the remote) whereas I believe most of the other units are only one device like a phone.
So your statement about 9 audio devices is not correct in my book. Up to 8 other intercom units but only 2 (or 3) audio devices like 2 phones or a phone and GPS.
According to the instructions it has to be a motorcycle GPS to work with voice instructions. I use a cheaper car Garmin so I don't BT to it, but just watch the screen.
The speed dial feature only allows 3 numbers to be saved whereas it has 10 presets for FM stations - I would like to have it the other way around 10 speed dials and 3 station presets.
That is one of the few negatives of the 20s.
There is an app for the unit which allows you to create group(s) of intercoms or adjust settings like how loud you have to talk over music to activate the intercom etc.
I have a GoPro but it doesn't have BT so I can't talk over videos while recording - but that is not the 20's fault, as if it was BT I assume I could talk to it while recording.
There are other cameras out there besides a GoPro that work pretty good and are less money too. So if the reason you would NEVER buy a GoPro is cost - there are other options.
I also don't video too often. I do listen to music on most rides and when someone else has an intercom it really makes the ride more enjoyable.
So for me, I would buy the 20s again.