I've been going to the Des Moines Quilt Show since I moved up to Iowa in 2011. As I'd never been to a quilt show I can't say whether its a good one compared to others or not. I tend to walk thru all the vendors's booths to see what they have that I can't get in my area. I also email my quilt machine dealer to order items I will pick up while I'm there to save on shipping fees. I can't say the prices at the show are any better than what I can get online so just to go and see all the quilts is a treat for me.
Houston Quilt Show is the one to go to from what I hear but it takes a couple days to go thru it all so take your walking shoes with you.