I'm going to try and not draw any direct comparisons between schools. But, I worked out Penn Med for 2 years and if you'd like to digest Stanford/Penn differences, feel free to PM me.
In most regards, I think the "one campus" community is better here than almost anywhere else I interviewed. Almost every student takes classes in other schools here, you have free, unlimited access to do so, and it's highly encouraged and easy to do (Wednesdays off, very little required class time second year). Many other schools give you this option...but it's not built into the curriculum, you are limited in your options if you don't want to fork over more $$$ to take outside classes, or you may have to travel far to go to another campus.
Given the location, there is also a huge on campus graduate community. I think this is really the distinguishing thing (and benefit) of a suburban campus (though, there are alternatively negatives to the suburban identity as well). This tends not to exist as much in urban campuses as most graduate students are scattered across the city in their living space. This is the one thing that is admittedly hard to see on interview day, but much more apparent once you get here. Most of the 1st and 2nd year class lives on campus, where you'll be placed with graduate students from all of the other schools at Stanford. My roommate is a law student for instance. There's a lot of grad community events as well- potlucks, ski trips, hiking outings, whale watching, running clubs, dinner clubs, etc. There was a DJ-ed Halloween Party for all grad students, graduate speed dating events, even Med/Business/Law school alumni events off-campus in SF- all things I've participated in just in my first quarter. A classmate of mine is working on a startup project with a computer science PhD student to design new iPad apps for medical students. They met after being roommates their first year. I've had friends who have started dating business students they met in the campus gym. It's these sort of connections/friendships that I think can really be fostered by the fact that interdisciplinary work doesn't just exist here (but is also ENCOURAGED), and that many graduate students live in close proximity to each other and attend many social events outside the academic realm.
I didn't really find this sort of "campus" community as strong (or easily available) at any other medical school I interviewed at. The great thing is...it's there if you want it. If you don't, staying within your med circle, going off campus (even living in the city) are all options to pursue your own social life too. As with many things in life, graduate school is what you make of it.
