It's on my list for next year. It's a lightweight ride - save for elevation - compared to a lot of what I've done and will be doing. The novelty of racing the train is the kicker.
FWIW: I raced the MTB XC race at the IHBC back in 1989 when I was a high schooler. It was still a NORBA race at that time. That old course (no longer possible to use because of development in Durango) was a kick in the pants: tons of flow, some fun jumps over water crossings, etc. And seeing some of the early legends of the sport - Tomac, Overend, Whitehead, Hans Rey - was worth the long drive from SLC.