I've watched some of the Brigham and the GWU review course videos and I would say that I personally like the Brigham a bit better. It's more streamlined and the speakers don't go into random tangents like the GWU does (I think GWU is structured more as a practice update for practicing heme-onc physicians, who also may or may not need to re-certify). GWU does invite a lot of heavy-hitter speakers though from a wide variety of institutions (and it's quite interesting even as a current fellow) whereas the Brigham is all HMS faculty. I don't know anything about MDA (and I think MSKCC also has one?).