Darrin Drader
Explorer
I think both books are very well done and actually compliment one another pretty well. I love the post apocalyptic genre and I like dark and gritty as opposed to 'wahoo!' There are things that I'm using from both books, but I have to admit that if forced to pick a favorite of the two, its definitely Darwin's World hardcover. There's just so much there. Its easy to believe that this is 3 Gamma Wordl books rolled up into one at only $10 more than the GW Player's Handbook. Besides that, the art's good, the new rules are excellent, and the world is well thought out (if you like dark and gritty rather than wahoo!). I would recommend that over many D20 books on the market in general these days.