Hello!
I am an international applicant with the same dilemma. I have been offered at CalTech and MIT too! The extremely small size of the ChemE Department at CalTech is a bit scary ain't it? Additionally, are any of you guys making MIT for the March 6-9 th weekend? It should be cool to catch up
I have been told(hearsay with inherent bias from grad student at MIT) that if broadness and flexibilty in deciding what you want to work on is a big factor in your decision, than MIT is the way to go. He claims that CalTech spends way more time doing very niche work!
Cheers