Basically what I'd hope for.
Slow, strong zombies that don't do incredible amounts of damage- so they're easy to take on one-by-one but if your building is beseiged by the zombies, you're best bet is to try and wait it out because trying to take them all on will just drain your ammo reserves.
Expect to see the Bluzone zombies some time in the near future, I may be testing them soon in the dev server.
Zombie defence in ACM city, anyone? Haha