I think whether one enjoys this book or not probably depends on the things one is interested in - other reviewers have complained about everything from the book being too introspective to being too much a list of Sacks' patients.
In part, it is both these things - as a book of case studies it cannot help being the latter, as a book written by someone who is himself an amateur musician as well as being knowledgeable about and intrigued by the neuroscience behind our musical brain, it is necessarily the former. However, neither of these things, for me, detracts in any way from the book.
If you have an interest in both science and music and enjoy books that are absorbing, sometimes densely written, very informative, and written by someone with both a wide knowledge of the subject and a keen curiosity about the whys and wherefores then you will probably enjoy this book just as much as I have, which is a great deal.
Not all of the cases have explanations, which sometimes makes them more intriguing - other, apparently stranger, cases, turn out to have fairly logical reasons. Sacks explores everything from the healing power of music to its capability of irritating or even tormenting those whose brains cannot control it, and the whole thing is intensely interesting for a musician with any interest in the science behind music.