I can give you a general, local flavor for BU:
I rotated with a BU resident at a local community hospital (well
regarded for cardiac, urology, transplant, SICU) -- she went there to get a month of transplant experience. She said she worked pretty hard, the attendings were so, so wrt to teaching, little didactics at the home base.
However, a caveat, because the BU program is changing --
attendings from from another local community hospital (who are mostly harvard trained, hospital well regarded for Ortho) have begun to become involved with the residency. Whether residents will rotate out to this hospital is not clear and how much role these attendings will play is not clear. It is hard to say where BU is headed, but considering where it's been, the change will undoubtedly be positive.