Matt,
I can't comment on Wade Hampton or Grandfather, but as far as Cascades is concerned, the first thing that struck me was the setting--I couldn't imagine it getting old. You've got the Allegheny's so close you could reach out and touch them, yet the course doesn't sit on too severe a piece of land--the terrain is perfect. I've played other mountain courses where the topography of the land didn't lend itself to great golf holes, but that is not the case at Cascades.
The vistas are wonderful, but you can't get so caught up in them that you lose concentration. The course does get tight in spots, but never overwhelms you into thinking you can't hit a fairway. Although the course is not overly long, it does present a stern test, and you can use the contours of the course to navigate your way through. The conditioning is immaculate, but I don't think my opinion of the course would change if that were not the case. One other point that struck me was that although the course could, and has held championship events, it is very playable for a less skilled player and won't beat up a higher handicap.