A couple guys did RAAM on Salsa Casserolls last year:

http://kaisercycling.com/2008granfondofixies.html

I have one and it's a nice ride. If I ever wanted to I could convert it to a nice geared touring bike since it has all the do-dads to just bolt things on. (They offer the same frame in a triple set up.)

I know a guy who just finished a 200k on a Masi. He's a roadie and bought the Pista first, but the geometry was not good for him.