I've already said this on another forum, but for those who don't read it, I'll repeat this here:
Those of you planning on doing this event solo, I really advise you bring a duallie
There's no technical descents which are going to really benefit with it as such, but where it's "useful" (a huge understatement) is how it's going to help the huge beating your body is going to take over the dry grass areas and some downhills. I raced this event last year on a hardtail and it was absolute torture come the 4 hour mark.
My goal this year, regardless of results, is to go out there and do consistent 24s-25s for the day laps, and 27s-28s for the night laps. Last year I was doing 26-28s during day and 32-34s at night, so there's a good benchmark there. This, of course, assumes the track is mostly similar.
Either way, I found it to be a good 'basic' track - good for endurance training, but nothing too technical. My only gripe was the entry cost is extremely steep for a 6 hour - especially if you're in a team.