I'm running RAID6 for data and RAID1 for metadata. Wanted the metadata replicated. So far I've had no HW failure situations and I have suffered a few power outages while I was away from home even though I have a backup battery.

Although these drives have surpassed 50,000 hours of running time, I am fairly certain the day of reckoning is coming, but I have backups and a plan to recover.

I may recover to something not BTRFS. Not sure just yet.