Hello! I actually really love Indiana University, as my sister went there for grad school and I'd visited the campus before. It's surprisingly beautiful and charming.
It's tough for me to speak about SPEA as I haven't visited any of the other similar programs (SNRE, FES, Nicholas, Bren) so am unable to compare them. However, I had a wonderful time at the Fall Experience Day at IU and really sensed the students' enthusiasm, intellect, and camaraderie. Unfortunately, I most likely will choose to enroll in a different program, as my interests are in climate change science and communication, and that's not really one of their strengths as compared to the other schools.
I was incredibly impressed by the effort SPEA put into recruiting students (heck, they convinced me to fly out from California to their weekday Fall Experience Day!) and making us feel very welcome while on campus. I was put up by a few current students, so got a sense of what life would be like if I chose to enroll. Honestly, the program logistics are so similar for these schools and there is a lot of overlap among applicants... so I'd guess that most the programs are just as great. So, I'd be honest with yourself about what program offers your ideal research project, concentration, strength, or faculty member, and go there.
Sorry I couldn't be so helpful; at the time of visiting, I was trying to decide whether I wanted to pursue a more professional or academic degree, and my visit to SPEA (and another more research-oriented school) helped me decide to go in the direction of a program like SPEA's. Hence me applying to the full suite of environmental management programs. But do you have any specific questions?
Anyway, thanks for distracting me for a bit. I think it's been a whole ten minutes since I've checked my email! It's 2:19 in New Haven...