Fwiw, I'm running a NAS on btrfs (on top of mdadm raid as I don't fully trust the btrfs raid, and the recovery tools seem worse). It seems to be working well so far.

Being able to do snapshots easily is really nice. I have a script that makes hourly snapshots and keeps the N latest, which protects me against a bunch of pebkac errors

I do periodic backups to non-btrfs storage though. I need backups anyway so it seemed like an easy way to de-risk