I'm finishing a 4 year program. I'm a lot more cynical about some things:
1) the med school's administration, and how much they care about you as a person versus accreditation, or versus statistics (eg match rate)
2) whenever a study comes out about a new drug, or a new application of an existing drug, and it's in anything less than Phase II OR the study is sponsored by Big Pharma, I just tune out and go digging for the flaws.
I think 2) is a good thing and 1) a sad reality of life.
I'm still idealistic about the following:
1) advocating passionately for your patients will help them get that extra care in an overstretched healthcare system
2) the stories and the struggles of my patients who are so much more resilient than I ever thought a human being could be. I see them everyday while I'm on service.