Hi! I wont recommend it without dedup. Check Copy-on-write file backups with ZFS in the manual. AFAIK this different on btrfs. Will store files many times.
We are using https://hup.hu/cikkek/20201202/openzfs_2_0 on linux, on ssd with dedup on and l2arc. 40 cores, 128 GB RAM, zil and arc on ssd. HDD storage.
IO speed impressive, but the backup sometimes feels sluggish. We could not figure out the reason yet.