Its really fun when you're in the mood for it. A good challenge and simple enough to pick up whenever you're in the mood for mindless slaughter with some absurd weapons. Leveling up can be slow and the amount of dlc weapons lowers my opinion some.
I lost 500 hours to this one. It abandons Killing Floor 1's horrific atmosphere and slower pace for pure adrenaline, fueled by metalcore and a massive arsenal. One of the best horde modes around, even now.