I'd probably echo what was said above about remaining open with regards to specialty. I was one of those people who was extremely set on one specialty and now I'm probably not going into it. I even did research for 2 yrs in said specialty. I also agree that MBA really isn't what you're looking for. I had a similar idea with regards to potentially getting an MBA, but I have met several people who run private practices who say it really isn't worth it. I would focus on really looking at the medical schools themselves, because the future really is variable. I was lucky in that I had a lot of great schools to choose from (including Penn), but I decided on Columbia. Both offer equally immense opportunities. I think it is safe to say that if you do moderately well at either place you will probably match into a top program in virtually any field. I've had the opportunity to help during match day for the 4th years and everyone I talked to matched into their top choice. There is just a feeling here at Columbia that if you follow the curriculum and do moderately well your success in matching is almost guaranteed. And while I don't go to Penn, I imagine the Penn students will tell you something similar. I think this a product of going to schools like Penn and Columbia which are honestly some of the best medical institutions in the western world. I wouldn't split hairs trying to analyze match lists when there are so many missing variables. If you feel like Penn is the only place that will make you happy, then I would go regardless of the money. However, I think you would be just as happy here at Columbia.
I'm finishing up my first year here at Columbia, and I can honestly say its been one of the best years of my life. It is an amazing place. I've already published a paper, classes are low stress (p/f and if you fail you just retake the exam), and I've made some really good friends (including a couple best friends). I've been able to hear and speak to so many expert researchers, including 3 noble laureates (2 of whom are alums). A lot of our prof and residents are Alumni. NYP generally prefers P&S graduates and there seems to be a pipeline for graduates to continue at Columbia. I've seen very few institutions that favor their own the way Columbia does. The research opportunities and funding for students are breathtaking, the dedication of our professors is unreal (one of our professors attends every class and takes notes for the class on each lecture), and NYP has so so so many clinical opportunities.
On top of that, you get to live in NYC. Something you might not have the opportunity to do again. And in terms of parties, there is nothing like going out with your classmates in NYC. The culture here is really low stress and people have so many interests outside of medicine. I've gone out more in the past year than I have in UG. Our class has gone to see the NY philharmonic, the Yankees, the Rangers, nutcracker at the NY Opera, wicked on broadway, and a ton of other stuff. People say you don't have time to go out in medical school, but at least at Columbia, you have so much time to explore the city. We also get to take advantage of the city within our curriculum, For example, we take narrative medicine classes (humanities-like classes) around NYC. I'm taking mine right now at the MOMA. And other students are at the MET, the Frick, ect.
I think Columbia is a really special place and I've done so many awesome things this year. I really feel like being here is a once in a lifetime opportunity. I think anyone would be happy here, and if you get to save an extra $100K & walk away from medical school DEBT FREE, I'm not sure how any sane person can turn down Columbia.