Thanks--I was indeed planning to go to Kentuck Knob as well.

I've been fascinated by Fallingwater ever since I saw a book about it years ago, and thought I would probably enjoy a longer, smaller tour. I rather doubt that the Sunset Tour is worth the extra $$ (it would take a lot of wine I'm not gonna be able to drink if I'm driving), but something about hanging around and pretending to be a guest at a party there seems appealing.