Any moon is going to provide you great instruction. Every moon is gonna be in a place you've never experienced. You'll be in good hands wherever you choose.
If you're gonna be in the states for a week, one location is good. However, let's say you were to stay for a month... Socal offers a good concentration of 8 moons. You could practically go spend a day a week at each of them and learn totally different techs at each. But that's super aggressive.