Pros:

great idea
challenging
special weapons strewn around the area
different from the other building maps

Cons:

no grace periods
impossible with bots
tanks spawn too often
needs tier one weapons at start for the difficulty regardless

Conclusion:

Great idea that needs expansion and work but problems are abound. Grace periods absolutely need to be added, as it's difficult to build things or heal when under constant attack by common infected. At the current moment, bots are just useless, while tanks spawn a little too often than most other maps. Brilliant idea, but these problems need to be remedied and fixed. Keep working and I'm sure this will be a great survival map.