Pros:

- Level design
Just class. Walking around through little mazes, while never getting really lost and come across a lot of areas you have been before (in the map itself or previous maps). It has been thought over and worked out very good.

- Atmospheric
It has the feeling of an infected city. Nicely done.

- Events
Just superb. Valve worthy. (Though maybe a bit repetitive)

- Exploding barrels
Nice add :)

Cons:

- Floating spawn (map 6)
See review of OwMyToe. We emptied several guns on Zoey. Than we thought: If we walk away far enough, she might be teleported towards us and solving the problem. So we went for the lift... Got stuck at first instance since she did not got teleported. We worked our way around it by climbing the ladder behind the elevator. But once we had to go for the subway tickets, there was no way around this anymore. In the meanwhile the SI and CI had a go at Zoey, but she took no damage. Just smiling a bit and that was it. So no finale was played... 

- CI spawning problems (Map 1)
The first gate we needed to open. 
We first set of the car alarm, than walked around a bit for pickups. After that we got ready to fight the horde and set of the switch. No horde though. It remained silent. 

Also the elevator should get a horde. We didn't see/hear it untill the elevator was down already and when we did, they didn't climb over the fences but ran across the bridge to be never seen again. 

- Nitpicking on design

All maps:
Some areas felt kinda empty. Maybe some walltags and a bit of trash would do the trick. Overall though this is not really a point of interest. (Map 1, right out the saferoom up towards the streets for example also in the offices, maybe a messageboard or two would be nice)

Some obstacles such as benches etc. you could walk through. 

Map 3:
The bridge appeared to be over a large swimming pool. The bridge was nicely made though, but made no sense being there ;-) Maybe this could be altered a bit.

- Further:
Maybe there are indeed to many medkits, ammo stacks and throwables. On the other hand: We didnt really mind since we were blasting our way through and could do with some ammostacks/throwables ;) :D

Barbed wire: Forgot the map, but it has been mentioned before here. You jump on it and randomly get boosted away.

The wheather, maybe it's an idea to let it rain. Since you got something of a "storm" going on with the thunder. (Rain is not needed for having thunder, but still ;)

Conclusion:

This is, next to I Hate Mountains, definately one of the best custom maps I've come across so far. It has been thought out and worked out very well. As the friend of OwMyToe said: This indeed could be a core-campaign. I can not start to imagine the amount of work that went into this. Only minus, and immediately a big one, is the floating spawn issue. That ended the party pre-mature. Nevertheless this still remains a very good campaign and with this bug fixed I'd say it's worth a 95% score easily. 

I really do hope Valve will notice this map sometime soon and just go for a little tweaking on this campaign... Although, they most likely never will, but it's actually worth it in my humble opinion. You've done a superb job on design and events here! Just please fix that floating spawn issue so me and my friends (and all others that play it/want to play it) can have another go at it and actually finish the map (more than once :)
Credits to you for this map, absolutely nice work!