I’ve been running btrfs on a little home Debian NAS for over a year now. I have no complaints - it’s been working smoothly, doing exactly what I want. I have a heterogeneous set of probably 6 discs, >20TB total, no problems.

*caveat: I’m using RAID 10, not a parity RAID. It could have problems with parity RAID. So? If you really really want RAID 5, then just use md to make your RAID 5 device and put btrfs on top.