I suppose it depends upon what your preferences are. I don't want to take anything away from what has already been said about Monroeville. If you want to see operating layouts you'll probably find more at Monroeville. However, if you're looking to find lots of toy trains and related items then you definitely should consider the Allentown Spring Thaw. The Allentown show features over 625 tables and 200+ dealers. It's all on one level. Here's the website.