That's good to know. but, while I like classical, I don't know if I want to commit to a fifty CD set. I do know that a few years* ago RCA was re-rereleasing their treasure trove of Living Stereo three channel recordings made in the fifties and sixties. Back then, they were strong proponents of having a center channel and made their recordings accordingly. Up until recently all those recordings were mixed down into two channels.
Now, with the advent of true multi channel playback, they re-released them in their original three channel format to be enjoyed as the original engineers intended..
The quality of sound these offer, particularly considering they were made 50 - 60 years ago is amazing. This shows that recording technology was more advanced than the playback tech.
As for multi-channel sound in general goes, it's a mixed bag. for classical, and most music, the sound is supposed to come from the front. I see it as useful in capturing the ambiance of the venue. Anything more seems, to me, would degrade the experience.
There are exceptions: A few years ago we attended a Paul Winter consort at The Cathedral of St. John the Divine where it started with a trumpet peal from the rear balcony and later, Mickey Hart was pulled from the rear to the front while banging on drums. Now, it that were recorded, MC would be totally valid.
Pop, OTOH, being basically a studio generated medium, is less stringent and can freely be mixed "for fun" to have "stuff" coming from all around you without destroying the "integrity" of the overall experience. Witness DSOTM wha the multi-channels actually become part of the performance itself.
*AFAICT, they still are. They are not hard to find.