I went to visit the schools a few months ago and here are my thoughts on each school, in the order visited. Would totally love to hear how other school visits went.
Berkeley: everyone was pretty down to earth, and I can definitely see myself being friends with the students.
Stanford: I felt that everyone was very chill yet super smart, which is I think is rare combo to find. The level of discussion in the classes were unpretentious and no one is trying to show off but you definitely can tell, just by the way folks spoke, that they were very educated and smart.
Wharton: another school where I felt the students were very smart but they were not as relaxed as the Stanford kids. Maybe it was the East Coast culture (I'm from West Coast), but I felt that the students were a little more cutthroat. I say this as a completely neutral comment; not a bad or good thing, but just what I felt. An interesting thing that I don't think I would've discovered unless I visited the school was the party culture. The student panel alluded to the social scene many times, and my friend who currently goes there say everyone just parties.
Columbia: I found that the student body was a good blend of laid-back students and gunners (aka alpha females/males). A lot of students talked about how they picked Columbia because they felt like they could make friends at the school. Combined with the awesome location of being in NY, I really liked Columbia.
HBS: very formal; when the instructor introduced us as the class visitors, the whole class gave us a standing ovation. So very well mannered students. Definite difference between HBS and GSB students, so you'll have to decide which one you like. I hear most folks only get into one and very rare get into both any lol.
MIT: first school to provide lunch to all visitors
. Then we got into small discussion groups for Q&A sessions with each student. By far, most participation by current students out of all of the schools we visited, which I appreciated that they'd give their time to prospective applicants like that. Their info sessions and what they told us was that MIT is very collaborative, and even though I didn't have enough time to see whether that was true or not, everything that happened on my visit day definitely made me feel like there's a environment there that would support such a claim.
That's all I got! Didn't go up to Tuck or visit the Chicago duo, so if anyone has any comments from their school visit, definitely chime in.