This book is a great resource to learn about the financial characteristics of the companies that Buffett bought during the middle years of his career (and the early years of his time at Berkshire). There are case studies ranging in size on just about every acquisition Buffett made in this period, focusing primarily on the financial statements. This is a great way to learn a little bit about the shared characteristics that many of the insurance and financial institutions that Buffett pursued.
Downsides to this book include very choppy writing ("due to the fact that"), uninspiring and flaccid commentary, and some data plucking. However, with that being said, I don't think the author was trying to create the greatest book ever written on Buffett. The objective was to provide numbers to pair with the acquisitions that were, prior to this writing, not readily available in one volume.
I am glad to have read it, but would only recommend to those most devoted Buffett followers/students.