This novel by Dennis Detwiller does one thing almost insanely well: it captures the feel of the Delta Green universe with its lack of good options and creeping insanity spiced with foolishness on the part of the actors.
It also does a wonderful job of intergrating Delta Green into Lovecraft's work via clear ties to at least two of the better known of Lovecraft's stories.
It does have some problems. First, there is the issue of typos and sloppy editing both of which are easily fixed, and spould have been before publication. Secondly, the characters are too often interchangible with little to make them seem alive. Oddly, the Nazis seem on avaerage better fleshed out than the OSS/Delta Green leads.
In the end, these issues are outweighed by the simply fact that it's a fun read, a real and serious page turner.