I would say I got much more out of the residency dinners / lunches in which residents but not faculty were present. Hopefully there they can be honest with you and tell you both good and bad things about their programs. At the official sanctioned events the faculty and residency want the program to look as good as possible and so you will not always get the full scoop.
For me what was most important was the quality of education, diversity of patient population and presenting complaints, and competence of my fellow residents as well as attendings, so I asked a lot of questions to that affect/did my research based on that.
I got the most out of talking to fourth year medical students who had done SubIs or other rotations at the programs, as they really knew what they were like (or if you can do those sorts of rotations yourself at the programs you are most interested in). Even a couple of days at a program will give you a much better idea of what it is like.
