I am a huge Beatles fan, watched the first 2 and thought it was stretched way to long. There were some shinning moments like Maxwell Silver Hammer which showed on the White LP and when Billy Preston arrived and everything got much tighter. Paul was in charge and the others were there in body prior to that point.
The high and low moments of the first 2 could have been shown in half the time.
I imagine part 3 will be the most interesting with the roof top concert.