The usual... UMass website, SDN, re-read AMCAS and secondary apps.
What impressed you positively?
How nice and accessible everyone was. Students seemed happy. Impressive match list. Interesting anatomy museum. Library looked like a great place to study. Lots of non-traditional students.
What impressed you negatively?
Nothing really...
What did you wish you had known ahead of time?
Nothing for myself. If you do not drive however, make sure to look up all the train and bus schedules ahead of time.