Due to budget costs instead of IOPS I've been using 2x6 striped mirror zfs pool to store photo/video. Upgrade two drives at a time every 1-2yrs & resilver. This approach lets me mix/match different new drive sizes over time. Been working well for over a decade.
Recently discovered used recertified/refurbished drives from ServerPartDeals/GoHardDrive for 1/3 the cost. Same price as my usual two drives upgrade I could buy six.
All drives fail new or used but unsure about AFR from SPD/GHD. 2x6 Mirrors allows 3 drive failure at best or 1 at worst. 2x6 RaidZ2 allows any 2 drive failure.
If I get a batch pair from SPD/GHD and both fail my mirrored pool is toast. If 1 dies then I am 1 drive away from total failure. Yes, I have physical media backup but restoration is a PITA.
Leaves me wondering if I should keep doing my mirrored setup or switch to RaidZ2?