While the book is well written, is is missing a significant amount of material in the 2.5 edition. All of the referenced tables and appendixes are missing. Now, to run a Darwin's World 2 game the four core books are needed the D20 Modern book is required and an exhaustive search on the internet for these missing tables is required. Now, these tables are impossible to find complete online and they are NOT included in the DW2.5 version of the PDF's. Wit the inclusion of those charts & tables I would recommend this, but without those charts & tables I would NOT recommend this product as in increased the frustration on the GM and the players when attempting to prepare for a campaign.
Good material, but it appears the presentation/publication to PDF is/was lacking.