This is an insightful book only if you read it the way Tim Ferris had meant it to be read.
He says in his introduction that this isn't the kind of book that you just go through. These are "tools" that you will need in your life someday or the other. The book is meant to be a guide inside the lifestyles of successful businessmen, productivity gurus, etc. who explain their tips and tricks for succeeding in their personal as well as professional life.
While at first this may seem a daunting book, its still fun to skim through every once in a while when you have the time. Keep in mind that this is a guide and you won't be disappointed.