I have the handbook, and would buy it again. That being said, my opinion is that it is very 'general' when discussing the evolution of the line. Don't get me wrong, it's worth reading ten or twelve times, and I have. It gives you just enough detail to get a person asking the specific questions that pertain to them and their own mission(s).

If there is a better option out there in print, I certainly have not heard mention of it.