I will say this though, although the mfgs of consumer NAS devices (QNAP, Synology, Lenovo/EMC, etc), often "recommend" "NAS-rated" drives, most owners/users of them, simply throw in the cheapest highest-capacity drives that they can afford. At least, I do. Which in my case, were 4x 5TB Seagate "Desktop" drives, shucked, and 4x WD Red 8TB, and 4x WD Red 10TB, again, all shucked from externals. They may not carry a warranty like the internal drives, but I doubt that they're much different in terms of quality, and for the price, you can just buy an extra to have a spare on hand, should one die. The NAS will run them in RAID-5 or RAID-10, so you don't have to worry so much about any one drive failing, due to redundancy. (Still should buy a high-capacity external drive, and make Cold Backups of your important NAS data. As we know, "RAID is NOT Backup".)