Overall, I rather liked this one. While I see the justice of some of the other reviewers' critiques, it seems to me that they were expecting an awful lot from a 40+ page supplement. It seems clear from the context of the book, that while the Oriental villain is FROM China (or at least the far east), he isn't supposed to be encountered IN China. He's here in the United States (or perhaps Great Britain) pursuing his nefarious ends, and to that end most of the material included in the supplement is highly useful, especially including the information on the Tongs and Chinatowns. The various minions and henchmen in the text take up a lot of space, but then, you would expect an Oriental mastermind to HAVE lot's of varied minions and henchmen, so again, it seems like no problem, and, while I will admit the fiction provided as an intro in the first ten pages took up a lot of space, it was well enough written that I really don't see it as a problem either.
Like the supplements on the Nazis and the Thugee, this one provides a sufficiency of information to permit you to at least establish the concept of the Fu Manchu-like villain; though if you plan to make such a villain a major part in your campaign, you'll clearly want to do a lot more research on the subjects briefly touched on in this volume -- just as you would need to with the Nazis and the Thugee. The technical detail provided gives you plenty of information to use in your search (the Wikipedia article on Mongolian Death Worms is an interesting read), as well as providing enough information to play even without exhaustive additional research. The illustrations are evocative and add to the feel of the material. As usual, DriveThru has done an excellent job reproducing the material, and the entire product was legible, readable and viewable. Overall, I have to give this one a "4."
[4 of 5 Stars!]