RRman - My guess is that it's the first annual. Depending on the success, I would expect there to be one next year. So there is no track record to base anything on. It is an any scale show, but there will be some 3 rail. I know 4 vendors, and three of them do 3 rail. The other is primarily HO and N. All tables are sold out.
Merlin from Caboose Stop is making he trip. Curious to see what he brings.
My long time acquaintance John Cartwright does pen and ink drawings of railroad depots in the five state area (MN, WI, IA, SD and ND). If he hasn't done them all yet, he's very close. I have over a dozen of his pieces hanging in my hallway. The art itself is fairly inexpensive, can't say the same about the framing, but I like to get a little fancy with it.
Even if the show isn't quite what you want, you would still have my offer of the picnic dinner and my layout, plus the other forum members to meet, on Saturday night. I recommend staying overnight in Hudson, WI, close to my place. That way, you're an hour closer to home. Add in a stop at the Twin Cities Model Railroad Museum along the way, and it's a pretty solid train weekend.
Give it some thought.