Andrew,
I still need to get up to Mystic Hills. So can't say which is better.
I don't disagree with you on some of the holes at Rock Hollow, but I think it may have been an old quarry, so there were definitely some lakes in play. I thought the use of the lakes was, for the most part, varied and very creative. A couple of the standard cape style holes but a couple very interesting, if not unforgiving holes. All in all a very fun course in my opinion.
And thanks Matt, Rock Hollow is a Tim Liddy course, but you can definitely see a bit of the Dye influence.