I own Ron's book and it has helped me quite a bit. As a new collector, it helped me get jump started in regards to building my knowledge base (still a long way to go
More specifically, it's prevented me from making some potentially costly mistakes. A few months back, I almost moved on a Ruth piece...which was JSA certed, and which got the PSA "likely genuine". Just before pulling the trigger on the deal, I reviewed Ron's book, and sure enough, he specifically discussed this exact piece in there. Obviously opinions do differ on this particular piece, but I was very appreciative to have all the info available before making an expensive decision.