Hank, whichever you choose, you will be happy with your smoker! Now, with that being said, I recommend going with at least the 2, and #3, if it's in the budget. Literally, let your budget decide the size. As Dave (Old Sarge) said, you can always smoke less in a bigger one!
I started out with a #1, and although it worked fantastic, I quickly regretted the size. I, like you, just didn't think I'd use it very much...Boy, was I wrong!! What I found is that it was so easy to use, I was soon smoking meat at least once a week, sometimes more! Prep & cleanup is easy, and that lends to more frequent use.
The #2 does everything I need, except full-size packer briskets (the whole brisket, usually 12-18 lbs) and whole racks of ribs. I LOVE the depth of the #3! I don't have to worry about the length of the meat, and that is great! The other advantage of a larger model is leftovers! If you have a vacuum sealer, it is much easier to smoke more, and freeze the leftovers.
Hang around here a bit before you decide, and ask lots of questions! Welcome to Club Lazy Q!!