I've played ZPS, very much enjoyed it. One of the best mods I have ever played in fact, but the L4D demo (10% of the full campaign, not including versus etc) has given me so far 17 hours of gaming brilliance. ZP has nothing on L4D, in re-playability and quality.
There were tons of bugs that have already been ironed out, you guys that didn't pre-order should be greatfull, this is working a bit like a beta.
Yip

Well, pre-beta...we're going to get the beta
