I am very positively surprised how good and useful this book is. It is certainly not what I was expecting – I think I assumed this book would consist of mostly flavor and not a lot of useful game mechanics. I wasn't really looking forward to this, but the actual book has convinced me otherwise. Well done! This is the best Player Companion in a long time, and certainly the best in the new format. Highly recommended.
Now, I finally know how expensive a tyrannosaur is, should I ever want to buy one! :)