Intermittent lurker here, so forgive the rambling and possible burying of the lead. Last paragraph is likely most of interest here but if I let myself edit this then I'll wind up never posting it.
I'm likely buying this set once I rejigger my "fun money queue." Between the UHD and the extended version on Blu (turns out the UHD digital copy comes with that, so I needn't have bought the disc), Superman has been a pricey indulgence this year. II & III is very, very tempting. Way back when, II was my favorite score; more so than the original. Just not sure I need III again. The UHD and it is nice to have the score (though not isolated) in hi-res surround. I do wish the vintage sound mix were lossless but it's also nice to have that. I also confess it feels like a missed opportunity not to have the isolated score (which I believe was included, in stereo, on the original DVD). While DVD-A is truly dead, it's my understanding that SACD actually still does pretty well in classical, jazz and other niches. In fact, Pink Floyd is about to reissue two OOP SACDs (Dark Side and Wish You Were Here) and a third (Animals) which has never been on the format at all. Yes, niches within niches among neighboring niches -- just like film scores. Thing is, Blu-ray Audio is fully compatible with Blu-ray; it's the same basic spec. There's no reason hi-res and/or surround can't be played on all Blu-ray hardware easily purchased for, what, $50US? Of course, that doesn't include full surround gear but that's a deeper topic for elsewhere. It's just an acknowledgement there are still complications.
I don't think I personally benefit much from hi-res but accept that others do. Likewise, I get the "we have two ears" dismissal. Forgive the diversion before returning to orchestras. Surround implementation can range from gimmicky (Flaming Lips' "Yoshimi") to "big stereo" (Beales' 1+ often gets this criticism), and points in between. One of my favorite albums, R.E.M.'s "Automatic for the People" received a 5.1 mix around 2000 or so and received a ground-up ATMOS (5.1.x) mix last year. When listening to either in 5.1 it is apparent that each was remixed differently and that each brings out elements that were buried (intentionally or otherwise). As a moderately critical listener without training, I find this wonderful. Not only is it immersive (to me) but for someone with an attentive but inexpert ear it can help me become more aware of elements I hadn't keyed into before. For some that's a distraction or even revisionist. For me it's refreshing. Then, when I return to stereo mixes (whether the original or new ones) it gives me a richer experience. Even if I still don't notice those elements in the stereo mix it somehow still feels fresher. Psychosomatic, maybe; subjective, certainly. Blasphemy... to some.
Okay. Orchestral. I have a handful of vintage RCA "Living Stereo" SACDs that are in 3.0 surround from the 1950s. In the case of the orchestral ones, it helps spreading the sections across an extra channel. Same even with something like Belafonte Live at Carnegie. It brings more presence. Last year, Deutsche Grammophone released two excellent surround sets on Blu-ray audio. One is Bernstein's complete Beethoven's symphonies in 5.1. The other is Steinberg conducting Holst's "Planets" and Strauss' "Zarathustra" in a vintage quad/4.0 mix. As with the handful of classical titles I have, the rears are used more to provide "presence" than anything else. For some, that's annoying; for others immersive. I rather like it, personally. Unlike DSP settings in a receiver, this bakes it in so there is no artifacting and -- more critically -- it has human artistic intent and engineering talent behind it, rather than an algorithm. Best of all, on the Blu-ray one can listen in surround, hi-res stereo or standard stereo because Blu-ray Audio is backwards compatible. This sets it apart from SACD and DVD-A's proprietary issues. It also means that, when titles are affordable (like "Planets" and, for the disc count, Beethoven -- and unlike R.E.M.!), people who are fine with 16/44.1 get what they want, as do the hi-res folks and the surround kooks like me. Best of all, one can upgrade or downgrade to suit their taste, budget, etc.).
For anyone interested, here's an interesting video about the process of prepping the Bernstein/Beethoven set. He discusses surround mid-way through:
All of this is to say, it's nice having the choice. It's too bad that economic realities of this licensed niche and the waning physical media market makes it less likely such options will arrive even though it seems this (and at least Star Trek: TMP) are ready to go in hi-res stereo. If/when they become downloadable, maybe I'll give them a shot. I did buy the most recent Star Wars hi-res download; it's more problematic history and edits make it harder for me to fully embrace it, though.