> All raid. Your odds of a dual fail failure are too high. These two sentences are in conflict. There are RAID modes where the failure of two drives is recover

> All raid. Your odds of a dual fail failure are too high. These two sentences are in conflict. There are RAID modes where the failure of two drives is recoverable. You probably know this, since you mention one of them in your next sentence. But maybe you don't realize that RAID 6 isn't the only way for an array to survive the failure of two drives, especially if the failures aren't simultaneous. You should read up on some storage systems beyond traditional hardware RAID and ZFS; there are quite a few interesting ideas out there you should open your mind to. Btrfs would be a great place to start your investigation.