Stop Making Sense (1984)

The Japanese LaserDisc sounds excellent. It has a stereo mix featuring three additional songs (Cities, Big Business/I Zimbra) that don't appear to have been crudely spliced in, so it's difficult to say whether this is indeed the theatrical mix. (Perhaps the theatrical mix was also prepared with these extra songs that were then cut out before the premiere, but I can't find any documentation supporting this.) 

Everything was recorded and mixed digitally (16/44), so there's no generational loss to contend with when comparing any of these mixes.

In ~1999, Jonathan Porath created two 5.1 mixes - one a "theatrical"/"film" mix and the other a "studio" mix, the latter intended to be a more produced and less 'live'-feeling mix. The two actually sound more alike than different. All audience noise is mixed extremely low and most of the hall ambience is gone. Everything sounds smoothed over and a bit dead. I find the more warts-and-all LD mix a lot more immersive. It's very 'of the time' (bright and '80s-sounding), but it feels right.

There are a few content differences, too. A handful I found (Palm blu-ray timecodes):

• 6:20: Byrne's feedback is completely different (louder and longer on the LD)
• 12:52: Byrne's "thank you" to the audience is a different take
• 48:10: Different instrumentation during the intro of This Must Be the Place
• The audience noise between most songs is typically very different (in addition to being much quieter in the 1999 mixes)
  

The 2.0 tracks on the blu-rays are basically the same as their 5.1 counterparts but in stereo - whether  direct mixdowns or concurrently made stereo mixes, I don't know.

This clip compares the LaserDisc track to the 2.0 Film Mix on the Palm blu-ray (which is, I'll reiterate, ~identical to the 5.1 Film Mix downmixed and grossly similar to the 5.1 Studio Mix):

There's strong limiting on both 5.1 tracks on the Palm blu-ray, but minimal actual clipping. The 5.1 Film Mix from the Second Sight blu-ray is like its Palm counterpart but with additional clipping. (I don't have the Second Sight Studio Mix -- a kind person sent me a single track from it -- but I suspect it also has extra clipping.)

Comparing waveforms and spectrals of different mixes is always of limited value, but here are some anyway (using the 2.0 Film Mix track from the Palm blu-ray and the LD track edited to match the blu-ray) to provide an overall representation of their dynamics and EQ:

Some quick waveforms of the 5.1 mixes: