It's the right sort of drive for an NVR or a CCTV recorder, which is the job WD rates it for. We list it because surveillance drives show up in any price-per-TB hunt. For a NAS array, though, you'd be running it off its rating. Five years of warranty is the other draw, and on a drive you'll leave spinning for most of a decade that's worth having.
!Watch out for
It isn't a NAS drive, and WD gives it no NAS bay rating. Building an array? Get a NAS or data-centre line, which comes with the rating. It's a 7,200 rpm drive and you'll hear it working.
There's no Backblaze data worth quoting here. On paper it makes 20 dB at idle and 36 dB seeking. WD lists 5.9 W at idle and 6.3 W working, which comes to 52 kWh a year for a drive that idles around the clock.
Specifications
Each value links to the Western Digital page or datasheet it came from.