Hi Stout! I've easily fit a 14+ lb turkey in the #2, no problem. You actually never want to smoke a turkey bigger than that due to food safety (the length of time it stays in the "danger zone" of 40-140). I've also fit a 12+ lb packer brisket in the 2, uncut. It may curl up the edges a bit, but they shrink fast.
I'll throw a wrinkle your way....The #2 is a great smoker, and can fit a lot of meat. But, if your budget allows, I really recommend the #3. If for nothing else, the depth. 20" will accomodate BIG packer briskets, multiple butts, and a lot of uncut full racks of ribs. You can always smoke less in the #3, but you can never smoke more in a #2. That amount of Q real estate can't be underestimated, and really pays off when you need it!