Does no one care about power consumption? Mechanical disks use, in my experience, 7-15w all day all the time just idling. If you live in a high energy cost area the ROI on going SSD can be as low as 3-4 years. If you can afford it, splurge for SSD. I spent ~$800 on two 8tb SSDs and I'm very happy with the choice.
If you live in a high energy cost area the ROI on going SSD can be as low as 3-4 years
~$800 on two 8tb SSDs
2 x 8tb HDDs is roughly $200USD
I don't know what kind of electricity prices you're paying, but to hit a 3 year ROI on your SSDs, you're paying at least $2.2USD/kWh, assuming the full 15W (232kWh/year total) consumption of the HDDs and assuming negligible power consumption from the SSDs.
Edit2: and to be fair I did take refurb HDD price. a refurb SSD is around $300 USD for 8tb, bringing the minimum power cost per kWh down to ~$1.7USD/kWh for a 3 year ROI.
I don't know if I'm alone on this, but I just bought the biggest 5400rpm HDD that was in my price range when I set up. Might notice the slower speed when doing a big data dump, but for streaming purposes you can run many 4k streams concurrently and the bottleneck would probably be your network speed before you hit a drive read bottleneck.
Had (and probably have it somewhere) a 2TB Toshiba drive for +5 years in my desktop as a games and programs data grave. Never once had an issue.
My current NAS drives are also Toshiba helium filled drives and though loud are okayish under light read operations.
I would get a recertified enterprise drive from Server Part Deals. Drives in the 12-18TB range currently have the best price per TB. Be sure to get a SATA drive if it's going in a desktop.
I've purchased refurb drives from both them and GoHardDrive.com. So far I'm 5/5 for a mix of Exos and HGST Ultrastar drives working perfectly out of the box.
Anytime these drives pop up on Slickdeals, the thread is full of 3 types of people: People who have never bought a refurb/recert drive but insist they are all going to burn your house down, people who have bought several with no issue, and people who have received a failing drive that the seller promptly replaced.
Was the drive scanned for errors before installing it? I’ve been running 2x8TB drives for about 1.5 years. If a drive fails, it is better to find out earlier while they are within warranty.