We did this run last year in late-May when the Crystal @ Avalanche gauge was ~900. Didn't do the falls though, it looks stomper at the bottom and the lead in did not look easy either. There's a corner, a quick step, then the big drop. Goto the page below and there's some pics of the falls, the munchy hole after at the bottom of said falls, and the other drop (6' ledge) on the run that the above post mentions. It's a fun run for the views and all, but for pure boating pleasure I thought Bogan Canyon and the Narrows were better. Take a big truck if you go up to the mill falls, too. Roads not gnarly, but more clearance is better. I would NOT take a car up there.
www.midgetspanking.com/Misc/index_3.htm