Recent grad, was on the admissions committee as a CA-3.
I agree with much of what's been said on this thread, except want to emphasize how difficult 99% of this stuff is to discern on an interview day no matter how many residents you talk to. This is especially true if you're trying to dissect out the differences between two good programs you are trying to choose between.
This is what I told applicants when they asked me how to choose a program, assuming you have options:
1) Geography
Pick a place you want to live for 4 years that makes sense for your situation. If your family is on the West coast, I'd personally think twice before picking an east coast program. There are so many great places to train- why pick one that's going to make getting home for a few days over the holidays a nightmare? Everybody's circumstances are different, but residency is a busy time, and it's hard to understand how that impacts your relationships when you're a medical student with (relatively) tons of freedom. Assuming you went straight through or took one gap year, we're talking about years 26-30 of your life here, the second half of a great decade. Spend it some place you really want to be.
2) Fit
Pick a place that vibes well with you, and beware the aspirational selection. By that I mean, if you don't really enjoy research and know you prefer a more hands-on teaching style, don't pick the super-prestigious program known for forcing their residents to publish like crazy and their "sink or swim" approach to intra-operative teaching! I see this constantly in residents picking specialties- they choose a path that matches an idealized version of who they wish they were, rather than one that is compatible with who they are.
3) Tiebreaker: Fellowships
If you need to pick between two strong programs and the above two items don't help you, go to the place that has the better fellowship in the subspecialty you think you might be interested in (if interested in fellowship). Fellowship match is more heavily influenced by connections than residency match, and many/most spots are filled internally (completely anecdotally- I have not attempted to confirm this with data). It's nice to have the option to stay put for a year if life is more complicated at the end of residency than it was at the beginning.
One final note: medical students are conditioned to believe there is one right answer to every question. Resist that mentality here: no spreadsheets! Truth is you'll probably interview at a few places that will make you happy and give you great training. If you try and make this decision based on stuff like prestige (overrated once you're in a certain tier), night float vs 24-hour call (you don't know what it's like to work either of them- I think 24-hour call >>>> night float!), and didactic schedules (they can and will change!) while ignoring the big-picture stuff I mentioned above, you're overthinking it.
Good luck.