A couple of days ago a WD Red 3TB in one my RN Duo v2's became unstable so I carried out some basic tests then removed it, I ordered a replacement WD 3TB Red the same day.
However, the thing that surprised me was that WD Red prices have not fallen at all, in fact they have gone up over the past 2 years by about 5%. You know, I would've thought that has Western Digital released bigger HDs over the past couple of years the smaller ones would get cheaper.
I guess it's all to do with supply and demand, and because the red HDs are in constant demand their prices will/can remain stable/firm and even increase over time.
Amazon US prices started out at about $200 in 2012, and dropped to about $100 about a year ago. They haven't moved off that level since then.
At the moment, WD Reds between 3 TB and 6 TB all cost roughly $30 per TB. That rises to about $45 per TB for both 2 TB and 8 TB models.
HAMR technology (heat assisted magnetic recording) should reach volume production soon, Seagate has been saying "volume shipments of 20TB+ drives in 2019; drives are built on the same automated assembly line as current products ... projected cost-per-TB path beats legacy PMR technology" for a while now. WDC is focused on MAMR (microwave assisted magnetic recording) instead, but are making similar statements on size/ship dates.
Though I have no crystal ball, I suspect that we'll see prices drop in the larger disks sizes (8-12 TB) before we see much change in 3 TB models.
