Karnazes's book is lots of fun. His story is interesting, his take on his own obsession reflects a fair amount of introspection, and it is filled with great anecdotes. As a life-long runner and veteran of nine marathons who is contemplating my first ultra, I found this very worthwhile reading. Some of the critics here at Amazon are an odd bunch. Sure Dean comes off a bit vain - to write a book about your own achievements requires a little bit of that, but to take a couple sentences from a book and make sweeping generalizations about his character defects is way off base. Lighten up and enjoy this inspiring story.