I've seen most of the documentaries out there which follow Warhol's life and work and attempt to account for his influence. I've also read a number of books which attempt the same, as well as those written by Warhol himself or by proxy. I was quite honestly surprised then that this documentary presented a great deal of his early work that was relatively unfamiliar or little seen. Because of this minute detail in the early years, his later work was given short-shrift. The 80's were breezed through. (Perhaps there are plans to flesh out the later years in the future).
The talking heads are wonderfully pretentious on occasion and fairly incisive on other occasions. Most humorously, one comment from some expert is often immediately contradicted by another expert; The scenes are juxtaposed to highlight this paradox of the Warhol mystique -- that it is everything and its opposite depending on who you ask. And that is usually what is great about the commentary on Warhol: his work is so immediate that the academic folk make a myth out of the man as much as or more than they do the work. Not that Warhol didn't nurture that myth.
The only striking problem with the film was the over-dramatization of Warhol's own words, many taken from his book 'The Philosophy of Andy Warhol: From A to B and Back Again'. I noticed the same lachrymose readings in Burns's recent documentary on Eugene O'Neill. This is much more sporadic in the Warhol film, but I found the O'Neill doc hard to watch because of all the (over)ACTING! by those who read from his plays.
P.S. -- Cheers to Robert Sean Leonard in both the mentioned documentaries. He was the most restrained and evocative in his readings.