Three other tires that have not been mentioned and are worth considering:
Panaracer Pasela TG
Panaracer (Pasela) T-Serve
Vittoria Voyager Hyper (formerly known as the Randonneur Hyper)
The Vittorias might be outside of your budget window and are more difficult to find than the Panaracers. I would also hesitate to use any of these tires for a heavily-loaded, multi-week tour, as the sidewalls and tread compound are probably not as durable as some of the more heavy-duty offerings from Schwalbe and Continental. For a shorter, less remote tour on a bike not loaded with the gear required to get you across the continent and beyond, though, they would, IMHO, be the preferred option. They will have less rotational inertia, roll slightly faster, and offer a more comfortable ride.
FWIW, here is a thought based upon my experience: I doubt that I could tell much of a difference between a $50 and a $100 derailleur, but between a $25 and a $50 tire? Almost certainly. It is really worth spending the money to get the tires best suited to your needs.