The USNWC has a challenge course, a private 37-acre island, the whitewater course which I believe is the only multi-channel whitewater course in the world (class III channel and class III/IV channel, as well as some channels leading into it that can be used for instruction), and several trails. I think that they have around 400 acres, and also have a few conference rooms, a restaurant, an outfitter's store, a large selection of demo boats, and is the training facility for several international slalom athletes. Since it is at least 2 hours to any other decent whitewater from Charlotte, it is a great facility, and you don't have to worry about shuttle, river hazards, water levels (you can call the store, and the water is normally consistent), etc. which also makes it one of the ideal spots to demo boats, because the water level doesn't change much during the day, unless the staff is trying to work on it. The eddies are terrible, but it also makes you that much better at catching eddies, and they put in rock climbing grips so you don't swirl around in the eddy.
The Penrith cost is closer to a whitewater course by itself, but the USNWC has so much more to offer than just whitewater. If you check out their Allsport pass on their site, you can see just how much they have (WW kayaking isn't on the allsport pass, but it is $20 for a day pass fyi).