Hi Jet Cheng,
So I did read this post and can offer a different perspective. I did the Columbia MAFN part-time while working in my current job an EQD trader.
The MAFN is pretty quantitative and mathematical, but there are electives with which you can widen your breadth (i.e. graduate level business school classes). In my MAFN, there were still a few part-time successful traders, HFT quants (which I consider Front Office), junior PMs, research, etc. Few people in the middle of a successful career will forgo earnings and career momentum to go back to graduate school. But there will be a few who might consider doing graduate school part-time; so you will have some BO guys at MAFN trying to transition to FO, but you will also have a few FO guys within Columbia MAFN. So be open to the fact that there will be some people within MAFN that you might want to emulate or ask advice from. I find it hard to believe that the student body at MIT Fin is going to be more FO heavy than Columbia MAFN (due to location & part-time student body at MAFN).
Also, on material studied, I took a few business and EMBA (Exec MBA) classes as electives (specifically on fundamental evaluation and earnings quality since I knew least about them); those classes were definitely top notch. Columbia EMBA on the basis of being in NYC offers great networking opportunities. In terms of location, New York itself is much stronger in terms of networking than Boston if you want to pursue finance after graduation; you can get a drink with contacts at ease. Be sure to properly price the value of location.
Again, I didn't study at or ever meet anyone from the MIT Fin program, so it's hard to compare. The best is for you to seek out someone you know and ask them; they might be able to give you best advice. Hope the helps.