08.27 (the joyeauto firmware) has been near perfect for me over the past week+. I've had no "black screen" incidents, Siri's announcements aren't getting cut off, it properly reconnects if disconnected, and GPS works OK (although it's still using my phone's GPS, not the car's). Plus it has the more attractive interface.
So while I'm a little upset that I can't flash any of the newer Carlinkit updates, if I had to get orphaned on a firmware 08.27 is performing extremely well for me.
I understand that some people stuck on 08.27 are having much less success with it though, so I really think Carlinkit needs to rectify this, since they posted that update to their normal firmware server. People with Carlinkit or Carplay2Air branded devices should be allowed to flash back to the normal Carlinkit firmware branch.