Regarding the Salsas, some of their official dealers listed on their website tell me by email they will pretty much build whatever components any desired Salsa frame.
Personally I use a vintage MTB for off road tours over trails not very rough and a Bruce Gordon BLT with 26 in wheels for pavement touring with only short side trips down logging roads (in order to camp in the forest away from the asphalt. Other more rugged bikes have been mentioned in this thread and if you don't mind ineffiecient pedaling over smooth surfaces, they would be a better choice for all round touring, I imagine. But I don't have the patience to drive a tanktruck down the highway.