This is mostly a bump for your post. :wink:
I am also interested in these programs and would like to know more info. From the research that I have done on scutwork.com and AMSA's site these are the impressions that I've gotten:
Tufts and BU are very rigorous programs where you may learn a lot but would also work a lot. St. Elizabeth may require you to do more scut work, but is less rigorous in terms of hours. Lahey has all the subspecialties and looks like a very good compromise. St. E has Cardio and Tufts fellows rotate in. Cambridge is very primary care and the hospital is small. Harvard programs are, well, Harvard programs. They take the cream of the crop and teach/torture them. They can afford to do whatever they want to do and still get THOUSANDS of applicants. Also, don't forget about Mt. Auburn in Cambridge. It is affiliated with Harvard, and pretty much that is its only claim to fame. Lahey I think is affiliated with Tufts. Feel free to email me if you have any other questions.
Dani