I can see the virtue of both authorized and unauthorized biographies. I guess I've always likened authorized bios to autobios, in the sense that though you would have access to more information, it would also seem that information is filtered to a greater extent. I'm not interested in reading gossip either, but as Isurvived said, I don't want to read anything where the subject is made out to be a godshead. Something as close to the truth as possible, regardless of whether the author had the cooperation of the subject or not is what I think best.
What I'm mostly interested in is approach. For example, I've just written a fictionalized account of a boxer's young life in the 1940's. I wanted to write in a language true to that time and place, not just in dialogue which would be a given, but also in the 3rd person prose and in the 1st person inserts I used in the ring and in other introspective parts of the story. To write it in a language that was more formal would have seemed condescending. The other truth is, to write in an overly simplistic language I think would have turned out to be patronizing. So I tried to walk the line between the two.
I'm interested if writers here have read bios, authorized or not, that also took into consideration the subject's time and place, character, lifestyle, etc, in the style used, the way that fiction does. Usually when I've read a biography, I can hear the author's voice foremost in the language. It is his/her take, and that is clear. What I'm interested in is a cross between biographies and fiction in approach and style. There would still be a distance, a discernible difference between subject and storyteller, in perspective, but not coming from such a foreign place.
I need another cup of coffee before I'm sure if that makes any sense or not...