This book is powerful, easy to read and to understand (even for those whose English is not their first language) and it has lots of practical advise that can be immediately put in place. I liked the fact that the author explained the power of self-discipline in all aspects of life. Some may find it contradictory (how does self-discipline help you to have the good life?) but after understanding the main concepts, it makes a lot of sense. Regardless of your personal philosophy, it is definitely a book to be read more than once and to be used for consultation.
For the advance self-improvement reader and overachiever, this book may not offer new concepts; however, I found the practical applications helpful and to the point.