I've been trying to look more into Hi-Res audio and as a result I think I've become a little more wary of it.
As Mr. Sato said, the general consensus seems to be that there is little to no audible difference between 44.1kHz/16bit, 48kHz/24bit and beyond. There are some exceptions such as live performances, but even then if the music hasn't been recorded using the proper high-resolution capable equipment then it isn't even really Hi-Res.
This automatically rules out any analog recordings or albums made using less than 24-bits and the first one to do so apparently wasn't until 1996. Despite that you can still find many "Hi-Res" albums being sold online even though they were created before 96/24 digital recording technology even existed. However, I'm not actually sure if this still applies to albums which were remastered later down the line, for example, the original
Greatest Hits album by
Queen was made before the introduction of 24-bit audio, however it was later remastered in 2011 so I'm uncertain if that means that the remaster could potentially be 24 bit. Either way, in scenarios such as that you could potentially be paying more for a larger Hi-Res file that isn't actually any better than what you would find on a CD.
To make matters worse it's apparently possible to fake Hi-Res audio by simply adding high frequency content back into a recording and depending on how well it was done it may be difficult to reliably detect a fake, especially if you're unaware of what method was used to do so. With all that said I think I'll continue to just stick with regular CDs for my own peace of mind.
Right now the only Hi-Res 24bit/96kHz soundtrack that I feel safe about purchasing is the Remastered soundtrack for the
Shadow of the Colossus Remake, mainly because it's only available in that format, thus there is no reason to have any reservations about it as there are no other alternatives.
Speaking of which, Mr. Sato, would you by chance know if any of the Hi-Res Final Fantasy albums featured on ototoy actually benefit from being 24bit/96kHz? I believe you worked on the soundtracks for TYPE-0 HD & Dissidia NT, correct? Both of those are exclusively Hi-Res on ototoy, while the Final Fantasy XIV albums listed only come in Hi-Res and 320kbps. I've been interested in those soundtracks (especially the XIV ones,) but not to the point where I felt the need to buy the physical CDs, hence it might be nice to get the Hi-Res digitals from ototoy, but I'd only be interested in doing so if there are any actual improvements to them when compared to their CD releases.