Oh WOW, I just recently bought this (like a few weeks ago) for full price! Dang! Win some and lose some, as we've all likely felt.
Anyway - I was hoping that this was going to be the studio tracks mixed in 5.1 but it's actually a live show (I see now that better research would have told me that) on the blu-ray, which disappointed me at first in theory, but then I put it on and had one of those "sitting there involuntarily smiling" moments as I dug in—just awed by the scale and audacity of the whole thing; it's really fun and awesome (like seeing one of the very first ZooTV shows back in '93 and having no idea what to expect—that's kinda the vibe I was getting). It's also a live show with some filmed storyline vignettes in between (this may not be news to you, but I'm actually not super familiar with Muse—I saw them open for U2 on the 360 tour and dug it, but saw they had a few 5.1 mixes, listened to this title on streaming and loved it, and that's how I picked it up).
SO, my feeling is that the mix on this sounds as good (if not better) than any live show in surround. The audience isn't always present but kinda comes in and out... I'm not sure if 100% of what is happening audio-wise is actually happening in real time at the concert (at the very least they're playing with a significant amount of sequencers and pre-recorded material) and there's scored studio stuff over the vignettes, but there are definitely some elements of percussion and synths and things that are discretely mixed in the rears...on the whole it really sounds, and looks, fantastic and is great fun!
I don't know a whole lot personally about the specifics regarding compression issues and numbers associated, I only know when things sound squashed to me, and this doesn't. Also FWIW, the packaging of the super deluxe is also great nostalgic fun and I give this band a lotta points for this whole concept. I'm glad there are still artists (over)reaching like this!
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