If you only want one book about Warhol, this seems a great choice. If you want many books about Warhol, you may find after reading them all that this is the one you'll rely on.
If you plan on becoming a great artist, plan on developing a great friendship with someone like Bourdon.
I've read other very good books about Warhol, including Bockris' "Warhol: The Biography", "Prince of Pop", "POPism" and "365 Takes", but remained quite puzzled about Warhol. Bourdon doesn't remove all the mystery, but he does reduce it considerably.
Besides being an excellent writer and so knowledgable about art, he was a close friend of Warhol's for more than 25 years. He's packed the book both with details and astute assessments. There's a lot of the movies in here, both about their contents and about why they made an impact. Many prints and people are pictured. He's provided contexts within the worlds of painting, of moviemaking, and of the culture at large rather than just describe what Warhol did. Although a friend, he's not afraid to note Warhol's failings, including his stinginess in paying assistants and the coldness he could exhibit to former friends.
Warhol's sad (to me) descent into hanging out with celebrities after the 60's is also well-covered.
Why would people hang out at the dumpy Silver Factory? Perhaps for a chance to get into his movies, perhaps to be invited to a group dinner that night, perhaps because they were wanted no where else, perhaps to score. What really happened to Edie Sedgwick? A book focused on her might tell you, but Bourdon manages to tell enough that you can realize the full tragedy.
This is the closest I've gotten to what made Warhol and his associates tick. It won't stop me from reading more about Warhol, but Bourdon has helped me make a big step in my understanding of Warhol. It's an exceptional book and hence seems a great value.