Got this from Dusty Groove. Listened to the "Is It Because I'm Black" lp, and was floored by how different he sounded from his later Hi Records years. The book alone is worth the price - apparently this was a project 4 years in the making, a lot of it spent weeding the truth from the fiction that Sly himself created. He was huge in Chicago, but any attempts to break through nationally were thwarted, always seeming by bad circumstances, the least of which by a man who used to work with him, Al Green.
Addition: Finished reading the booklet last night, which is on par with the research and reviews given in a standard Mosaic box. I'm really digging the "Is It Because I'm Black?" session.