It will probably be useful to someone for a while, but prices are pretty fluid.
There is somewhat of an apples vs oranges issue, in that you are listing different types of hard drives, which have quite different design characteristics to make them suitable for particular uses. The "black" version in your list has a dual cache design that is going to be particularly useful in massive data transfer situations, as well as faster speed. The NAS versions are generally designed to be used in fault tolerant arrays in servers, so they limit retries if data is not retrieved the first time, on the assumption that the drive can be faulted and the data retrieved from another drive faster than by re-reading it too many times. The purples are specifically designed to record constant video input from surveillance systems, and are much more error tolerant than typical drives since stopping the drive on error will result in some data loss, and data errors will not be as critical in producing usable images. And of course the green drives are designed to power down, slow or stop, when demand is low to conserve power.
For error free real time audio using a single drive (not in an array) in a dedicated DAW, a standard desktop drive or possibly one of the black drives make sense. Green drives are suitable for backups. I would not use the red or NAS drives except in an array, and I would not use the purple drives at all for any general storage.