A friend of mine built a Vaya up and it is a very nice bike. Overall, it kind of splits the difference between by first generation Fargo and the new Casseroll. I like the ride of my Casseroll slightly better, but the lighter weight of the Vaya over the Fargo is nice. Overall, a very nice bike for what you want to do.

Here is a link to a discussion of various Vaya builds folks have done:

http://forums.mtbr.com/salsa/vaya-builds-595223.html