I found the Master the LSAT book not useful at all for logic games. The Logic Games Book by Powerscore was much better. I thought the game notations in "master" were much more complicated than LGB's.
However, I think it's helpful with LR and it was a nice supplement to my Powerscore studying. Nothing beats a full-length PowerScore prep class. NO I don't work for PS, just a very satisfied customer.
I haven't marked up the book so I will be selling it after I finish the June LSAT.