I'm in my mid-50's and recently paddled the big ditch in an RPM. I'm convinced it's the best boat ever made for that sort of trip - big water, fast current, not very difficult. The RPM has exceptional hull speed, it's comfortable, and easy to roll. The whitewater isn't difficult, but the current is very fast so you really want a boat that helps you catch waves. Even with a fast boat, you'll probably miss most of the waves you try to catch.
In my opinion, none of the boats you listed fits the bill as a great GC kayak. Of the boats you listed, I'd probably just take which ever one is most comfortable. But if you can borrow something that's fast, I'd recommend doing so, especially if this might be a once in a lifetime trip - go for it!