Hi, I've applied for the PhD program in pure mathematics beginning in the upcoming fall term. I've been lucky enough to receive funded offers from Michigan and Penn as well as a waitlisting at Yale. I have been trying to decide where I should go for a long time now. My interests are quite broad and mostly in geometry and topology. I've had email exchanges with professors at Michigan and Penn and was very happy with both exchanges in terms of how I got along with them and what reading they recommended. From the department websites, Michigan seems to have a significantly larger department than both Penn and Yale. All three places have professors with whom I would love to work though my currently (this could change with more information) favourite possible advisor/project combination is at Michigan. I've had contact with graduate students at Michigan and was happy with what they said about the place and program but have not had contact with graduate students at Penn yet.
Suppose that I receive an offer also from Yale. Given everything, it seems to me that of the three places, Michigan is where I should go, however I do not feel certain about this just yet. I am certainly affected by the prestige associated purely to the names Yale and Penn, which I feel is almost certainly superficial of me but I'm also wondering whether the general, non-program specific, prestige is there for a reason, could imply positive things about their programs and so shouldn't be ignored?
Any pertinent information comparing the programs at Michigan, Penn and Yale and any thoughts at all on where I should attend will be greatly appreciated.