I bought both games last year at GenCon and really like each. Personal opinions on game mechanics and content aside, I have to say that the single worst thing about Outbreak: Undead is the font choice. It's a handwritten style and is used throughout the enormous book. If it was used sparingly here and there, fine. But its just too hard to read in that quantity. Frankly, it's the reason I've put it on the shelf and have gone with All Flesh as my zombie game of choice. If the publishers of O:U ever come out with a revised version, I'll buy it and I'm sure love it. Until then, AFMBE it is.
'Outbreak: Undead' is a Zombie Survival Simulation RPG that is not only fun, but an essential step in surviving the Undead. We at Hunters Books have provided the most dramatic, effective, and above all realistic means in which to (safely) simulate the events of a zombie uprising and try your chances at survival! I am a GM who has been running Outbreak: Undead and Outbreak: Deep Space for at least 4 years now, both for my friends and at various cons, including Gen Con. I was one of the beta testers on Outbreak: Deep Space and Outbreak: Undead 2ed. I have written, as of now, 7 custom scenarios.