My boyfriend and I drove up here on a sunny fall day, not really knowing what to expect. We ended up having the most amazing time walking around and enjoying the sculptures, the mountain views, and the endless rolling hills littered with works of art. This is one of the coolest places I've been - you can just wander around for an hour or two, or make it a full day trip complete with a picnic. Even if you're not into sculpture, it's definitely worth going to, just to hang out in a drop-dead gorgeous setting.
Pros: really unique, gorgeous views, impressive collection