I have a 30K I've been testing for a review. Mesh intercom is a cool technology, does a better job at keeping a group connected than Bluetooth intercom. The 30K is otherwise quite similar to the 20S Evo (latest iteration of the 20S), so you can connected it via Bluetooth to your phone, GPS, etc. One thing I like about the 20S and 30K is you can connect in-ear speakers to the audio out jack and get way better sound quality than the helmet speakers. If you wear earplugs anyway, in-ear speakers can provide the sound attenuation you want plus you can listen to music or radio or intercom if you like.
I have no experience with Cadro Scala PackTalk so can't help you there.
--> FOLLOW UP: The 30K does not have Audio Multitasking in Bluetooth Intercom mode, which means if you connect to another BT intercom (like a Sena 20S) you can't have music playing in the background drop down automatically when you talk on BT intercom. No problem if you're connected on Mesh Intercom to another 30K, but there aren't a lot of those out there yet.
On a recent ride to Moonshine it was annoying that if I wanted to talk to another rider on an open BT intercom channel, I couldn't have music playing. If I wanted to talk via intercom I had to push the button on, then talk, then push it off if I wanted to hear music again. Reached out to Sena and they explained that on the 30K they did not include the Audio Multitasking functionality for BT intercom, only for Mesh intercom. I asked them to rethink that decision, citing the small number of 30K users available to connect with via Mesh. I asked if they could offer a firmware update to include Audio Multitasking for BT intercom. Not that they'll do what I ask, but I put it out there.