I installed TrueNAS core beta on one of my machines today. It certainly is more refined than it used to be, I think the last time I installed FreeNAS was 10.4 or something like that. I had no issues getting it to install on my Ryzen 7 3700X box. I'm running initial tweaks on the file system and will be running some benchmarks to see how it compares to my Debian Buster w/ ZFS and NFS install.