There's a lot to like here if you're already a fan — or at least, have some interest. Probably not too much if neither of those apply.
It has interviews with those who are still with us (or who were when it was made). Not just John Cale, Moe Tucker, Doug Yule, but members of Andy Warhol's Factory crew (the 'Superstars'), like Mary Woronov and Gerard Malanga.
I'd like to have heard more of the songs, especially the less well-known ones, and seen more footage of them, such as there is. It uses the documentary style that just films people speaking and edits those interviews together. That has a certain power, but I feel it might have helped to have a narrative, a voiceover elaborating on the story.