UMass all the way! Ride that in-state tuition for all it's worth. It's an awesome school and you'll get a stellar education that will make you competitive for tons of med schools, including a big boost from UMass Med, which is a much more worthwhile investment if you want to match back into MA in the future. It also gives you a chance to explore other classes and things you like to do outside of medicine, juuuust in case you decide medicine might not be right for you. Best of luck!