I worked 3 or 4 of them for the Rocky Mtn Elk Foundation and was glad I got in for free after checking out all of the vendors/exhibits each year. For what they chage for entry I wouldn't have felt I'd gotten my moneys worth. But then again, I feel this way at most gun shows I visit.

ETA: In the interest of total disclosure, fishing, particularly fly fishing, is a big item at the ISE. I'd mch rather just fish than stand arnd and talk about it. Additionally, due to financial limitations, all of the hunting/fishing guides and premium hunting/fishing access vendors do nothing for me.