I've never subscribed to "Hi-Res" music, most CDs sound great with good speakers, you don't actually need a better source file most of the time rather you need a good system. Also on the few times that I've compared "Hi-Res" files it just seems to me that there is a lot more HF in the file. Have not gone through the link.
Correct, I would focus on the system rather than chasing hi res files which are unwieldy to say the least. Redbook is optimal but Spotify 320kbps streams are plenty good. Since gaining access to Spotify I hardly listen to my collection of Flacs on the external drive. I have noticed I am playing those albums I own also off Spotify. If there is a difference between the Flac vs Spotify stream, I can’t seem to notice because I am having too much fun with my current system.