Good to know. I see bluez-5.21-r1 is in the Entropy Limbo repository, so you should be getting it in the Sabayon Weekly repository shortly, and perhaps that version will solve your problem with BlueDevil (or Bluez, I'm not sure which) forgetting your Note 3.
The only minor problem with bluez-5.21-r1 is that the directory you specify for saving downloaded files is ignored and all the files are instead saved in your $HOME directory (i.e. all files I send from my phone to my laptop are saved in /home/fitzcarraldo/ even though I specified a different directory via BlueDevil). But that is hardly important considering that file transfers did not work at all for me before Bluez 5.21-r1 was released (there was a bug in Bluez-5.21 for OpenRC users which prevented file transfers). Anyway, I expect the target directory bug will be fixed in Bluez 5.22.
Bluetooth in Linux is a pain in the neck. I wonder how long before it breaks again?