I've read most but not all of the 33 1/3 books and I've enjoyed most of them. Obviously it varies depending on the author and the album in question, but I think they have a pretty good ratio of success to failure. I haven't read too many on bands or albums I don't like, but I can only think of a few disappointments, and those tend to be the more dry, academic volumes (the ones that come to mind first are the volumes on the Ramones debut and Jethro Tull's Aqualung).