although I had friends who had. I was told by them that it only had a couple of Class II rapids on its 6 3/4 mile length. The general consensus seemed to be that if you wanted to do a whitewater run the 9 mile stretch from White Haven to Rockport was much better. I also heard a couple of stories about hostile fishermen.
There is what seems to be a reasonably good description on the American Whitewater site: http://www.americanwhitewater.org/content/River/detail/id/3582/
Note that as of 5 years ago there were access issues for this section. I don't know if that has changed or not. You might consider checking with the Park rangers at Rockport.
Full Size Sail Rig
Kayak & Canoe Outriggers
EZ-Dock modular docks