If I were you, I would spend some time shopping at the local shops. Wheelworks is my shop of choice in the greater Boston area, but International has its supporters, as does Back Bay. I heard about a new shop- very commuter oriented opening in Somerville recently,so maybe check them out as well. Don't worry about brand- anything in a real bike shop is going to be of good quality. It is ALL ABOUT FIT & FEEL. Ride everything they suggest, and everything that looks like it might be right. Ask questions- lots of questions, even if you think they are dumb questions. The right bike will tell you it is the right bike.