I give it Two three thumbs up.
The first part went live at 2AM (Austin time) last night, so I decided to stay up and just watch the first few minutes to get a feel for it.
I couldn't look away...and it was 2.5 hours. I didn't get to bed until 5AM, and company comes over in a few hours. I regret nothing.
For non-fans, like my wife and kids, it would probably be boring as hell, but for the millions, like me, who know every f-ing song, it was fascinating.
The whole show is based on their rehearsal sessions when they were trying to come up with new songs for a Live TV Special/New Album/Background Documentary. They would be just screwing around and suddenly one of them would drop the chord progression to some masterpiece. George came in one morning and was like Hey Ringo, check out the song I wrote last night... he plays I, me, mine.
The biggest thing I learned from part 1 was that George could be a passive aggressive asshole.