It was the hardest thing I've done, and I have no desire to do it again. If you want a very difficult race, going up and down trail hills for 26.2 miles at an altitude making it difficult to breath standing, this is it! Otherwise look elsewhere.
The race set up was fine, aid stations often enough--and they stayed open even to the end of the slow runners (I was 4th from last, but out of 50!). Very beautiful. Need to be careful with every foot placement for 26.2 miles. It's a 13 miles figure 8 you do twice...so once you get done with the first half you know exactly what hell is in store for you in the second half. Due to my inability to breath in the second loop, I ended up walking all uphills.
Know what you're in for. Read other reviews, don't think "it'll be fine," because it won't.