I have ridden in the Moab Century, but the routes were different that year. It looks like this year, the metric includes "Big Nasty" La Sal, while the full century includes the ride to Dead Horse Point (which is gorgeous with manageable climbing) and a spur along the River Portal. I did the Dead Horse Point ride during this spring's Skinny Tire Festival and loved it. I don't know that I would have had enough legs in me to add the River Portal spur (even though it's flat) but I'm not that strong of a rider (plus I still had winter legs). Did you check out their website yet? It has a nice video where you can see the gorgeous scenery.
http://skinnytireevents.com/content/section/12/140/