Replayability is decent, there is a horde mode and of course playing through with friends who haven't played it before can be quite fun. Or going for challenge type play through with the hardest difficulty and max wave on zombies.

I wouldn't compare it to L4D2 or Killing Floor I don't think it's close enough to either of those.

The pistols don't offer great variety but the revolver plays much differently than the colt or Luger. The rifles vary greatly, some are semi-auto but less powerful where as other have a higher muzzle velocity meaning less bullet drop. As far as secondaries some prefer the shotgun, some prefer Thompson M1 or PPSH-41. There is also a special shotgun available as a pick up in certain maps called the preacher which is very powerful but super limited ammo. Oh and the Panzerfaust which is overpowered and is really useful in the game.

Replayability is decent, there is a horde mode and of course playing through with friends who haven't played it before can be quite fun. Or going for challenge type play through with the hardest difficulty and max wave on zombies. I wouldn't compare it to L4D2 or Killing Floor I don't think it's close enough to either of those. The pistols don't offer great variety but the revolver plays much differently than the colt or Luger. The rifles vary greatly, some are semi-auto but less powerful where as other have a higher muzzle velocity meaning less bullet drop. As far as secondaries some prefer the shotgun, some prefer Thompson M1 or PPSH-41. There is also a special shotgun available as a pick up in certain maps called the preacher which is very powerful but super limited ammo. Oh and the Panzerfaust which is overpowered and is really useful in the game.