Pros:

Plenty of weapons
Setting is different than usual stuff made

Cons:

Limited fighting area
Less horde at top

Conclusion:

Tower design is good, but the map basically says "fight at the top until you die". You can last a long time up at the top just using AI bots in single player. Only small amount of horde attack up there, but the special infected do make up for it after a while when approaching gold.