I really liked both of these programs, overall. One thing that I noticed was that at Rainbow, they implemented the silver team, to give 2nd year residents some more autonomy- I didn't get a clear picture as to whether MCW residents feel like they have autonomy or not. Loved MCW's 16th Street Clinic, since I'm interested in working with a Spanish-speaking population. I liked that Rainbow residents got a ton of electives in their 3rd year... at MCW you spent like 5 months as the ward senior in 3rd year, and I think I would want more elective time that year, before graduating.
Rainbow surprised me with their phlebotomy schedule... someone mentioned that they don't have night phlebotomy coverage in some units (NICU I think), so I guess residents might have to do blood draws then? (Pretty minor).
I thought everyone I met at both programs was really nice and everyone seemed pretty happy. I got the impression that I'd be happy at either program, though I liked Milwaukee more than Cleveland in terms of quality of life.