big john: The Cool Breeze event is on my bucket list for next year.
Do it! It's one of my favorite organized rides, done it 10 times. It's a well thought out route and the support is good. I would suggest the low land 100 for your first time, my group does a modified version of the double metric.
When that one gets to be old hat, let me know and I'll tell you about some tough ones. Of course, I don't love the ride unless the food is good.