MDD sells refurbished drives for cheap on Amazon. The ones I got look brand new and pass extended SMART tests with flying colors. I just got a 14tb mirror for well less than a single 14tb new.
Discussion
I've been trying to decide whether I want to go the second-hand route. It's *probably* fine, since the whole point of a multi-bay NAS is redundancy, but it still feels wrong
On paper, MDD has a 5yr warranty on many of their drives. That is far better than any new drives give you. Reviews say they have been great on DOA drives and other short life failures, so the only concern is really if they are around in 5 years.