"Good core concept, but repeated incessantly"
The core concept is good, but they did not have enough content to fill a book. I believe they could have conveyed the entire premise in two chapters. They nearly verbatim repeated themselves, which became quite obnoxious.
"Simply Excellent"
I great book to make you think about your own business and humbly acknowledge how far you have to go.
Enthusiastic without going over-the-top