I’m in similar boat- experimenting with a pi4.
I’ve literally only been running for past 2 hours, but it looks like it runs fine for me under latest raspbian, but you have to tell it to run the new beta Aarch64 kernel
Backup everything first - just in case!
Add arm_64bit=1 to the very end of /boot/config.txt , then do the usual to update, sudo apt-get update ; sudo apt-get upgrade , then reboot.
After it comes back up, run uname -a to confirm it now shows aarch64
Linux raspiM 4.19.118-v8+ #1311 SMP PREEMPT Mon Apr 27 14:32:38 BST 2020 aarch64 GNU/Linux
From there I just followed the steps on this page:
