Oh yeah I forgot to say, use this:
Tier 1: Chrome Shotgun
Tier 2: Ak-47
Sidearm: Magnum, Crowbar
Grenade: Bile Bomb
I love the sastifaction with the chrome shotguns, seeing blood go everywhere and a huge gapping hole in the zombies is awesome. The Ak-47 is just perfect for clearing out hordes and killing tanks, and it looks awesome too. With magnums it's just fun to see the results when you shoot a zombie and crowbars are awesome when you hit a chunk of a zombie's head off. Bile bombs are the coolest looking, and are perfect for slowing down tanks for your friends to hit.