I went ahead and upgraded from 6.9 to 6.10 yesterday and crossed my fingers that the NFS mounts would not break.
Great news... nothing broke! Literally nothing NFS related broke at all. It was wonderful.
If anyone else is in this predicament and holding back upgrading to 6.10 because of the change from NFSv3 to NFSv4, I just wanted to share that for me it was a seamless experience.
It appears that Unraid does not export a root filesystem, so there is no pseudofilesystem to think about. I feel like this is fine in an Unraid environment where your exports are all already stored under /mnt/user/ anyways, and you're really not supposed to manage your /etc/exports file manually.
