My opinion: they are great!
The work of Mr. Fairbairn compiling the data, the historical references, the geography and his excellence in writing and even working of the little details of what happened during the development of the game is amazing and shows a great devotion to the work and to the Go.
You will have access not only to the analysis compiled by the author, but also a better understanding of Go history, anecdotes and sometimes, humor ("Fujisawa Kuranosuke is very good at fuseki" & "White 8 is bad"
Dkzn