Thank you to everyone who replied to this thread. It really helps to get feedback on my decision. I think that Caltech might be disastrous...The professors don't seem terribly supportive, the program requires chemistry knowledge that I don't have, and the profs have been largely unresponsive to my questions. Actually, I'm also a little worried about all the recent suicides at Caltech. Two undergrads, one graduate student, and the famous chair of the Physics, Mathematics, and Astronomy division? It just confirms what I saw when I visited...that everyone there is under a great deal of stress. Not the most pleasant environment for a PhD. I'm leaning towards UWashington right now actually.