RideRed, as for whether to attend the Iowa Reptile Show and Sale or NARBC @ Tinley, my suggestion:
Go to both.
They are pretty different. I wouldn't drive 500 miles for the one in Iowa, but since you're located fairly close it's worth the gas if you're looking to do some shopping/looking/entertaining yourself for the afternoon. It was pretty small, but I made a few essential pickups for my collection there. For a small show I was surprised at some of the well known and high quality guys who were there.
NARBC however is a true experience. It's big, worth checking out for a whole day, and you can meet some really cool people there. There are typically some talks and events, and an evening auction. I'm not planning on making any purchases (go ahead and lol at me right now, like THAT is going to happen once I get there) at the one coming up later this year, but still I am planning on making the drive from Minneapolis and staying overnight at a hotel. The fun of the show is worth the travel expenses for me.