Not sure if its the largest, but it is huge.
If you want to see EVERYTHING, it might take more than 2 days. They usually bundle campers together by manufacturer, rather than putting all the fifth wheels together.
My suggestion is to try to narrow down the brands that interest you and focus on them and try to find a model that interests you. Its one thing to casually be looking through campers, its another to be focused on buying something specific.
If you can narrow down to certain features, length, weight and brands, then its pretty easy to look through Hershey in a day.
Either way, Hershey will give you a very large selection of options in one place. Its worthwhile for that.