It is a lot of fun, but Otis is very annoying, and all the mission text is extremly tiny.  Its fun mowing down zombies, and getting acheivements.  I can't say that this is worth its $59.99 at this time, maybe if there was an update, or something extra that came with it, I may consider this a purchase game.  As for now I consider it a rent until some improvements are hopefully made to this otherwise zombie killing game for hours of entertainment.