I've been looking at the combo cooker myself for camping as I like the versatility. If you want to see what it can do, check out Cowgirl's blog, she uses one pretty regularly from the looks of all of her awesome cooks.
As far as the Dutch Oven goes, you need to decide how you are going to be cooking with it outdoors. If you have a camp stove for instance, you are going to want a Dutch Oven:
If you are wanting to cook over coals, then you want a Camp Oven (its the one with feet that you can put coals on top of).
Either way, I'd get one with a bail handle. You won't regret having the handle for one handed transport of the Dutch Oven...it also helps in hanging the Dutch Oven from a shepard's hook or a tripod.