Just watched all of this for the first time, on Blu Ray... I have to say it was mighty enjoyable and better than I expected.
I mean, sure the roster is pretty great, especially for the time, but you just never know so my expectations were tempered. But for instance, I've always been kinda lukewarm on Jefferson Airplane in general (although I had aunts and uncles that were there at the beginning and they freaking LOVED them, which I never really got although I like Surrealistic Pillow well enough)—but watching this along with the music certainly made me understand a little more where they were coming from... though I still don't get the appeal of Country Joe and The Fish.
The performance from Janis & Big Brother is absolutely stellar, the Mamas & The Papas come off really well... and then of course Otis takes the stage and the whole thing goes up ten notches in power, presence, and performance... and Jimi, of course.
Great sense of time and place with the B-roll footage (including shots of Jimi, Mama Cass and others in the crowd, reacting to the stage), a whole disc devoted to out-take performances not used in the movie with super interesting stuff like Laura Nyro, Quicksilver Messenger Service, a very young Grateful Dead with a beardless Jerry and Pigpen on the organ, the whole Al Kooper/Blues Project/Electric Flag/Butterfield Blues Band conglomerate... a really young Steve Miller... even though it's easy to see why a lot of this stuff didn't make the cut (snipped beginnings and endings, some meandering and pointless jamming, some pretty out-of-tune singing, etc., etc.)
And if Tiny Tim singing wartime classics in the green room lit by only a cigarette lighter is your thing? That's in there too.
Not much of a surround mix to speak of although it all sounds pretty fantastic due to the age and circumstances! Will watch this one again.