Late to the party... but wanted to throw my 2 cents in regarding the differences between M2Fs and F2Ms.
It is indeed true that F2Ms can pass more successfully once on hormones (and I say once on hormones because pre-T, most F2Ms are just labeled as being 'dykes' by society, as they still retain feminine features but dress and behave masculinely). Most F2Ms look like young men (which is annoying if you're going on 30 and people think you're 17/18 and treat you as such), but most can pass in society.
It's also true that it's harder for M2Fs to pass because of the irreversible effects of testosterone. Not many can pull it off (passing), unless they undergo a lot of surgeries. Once those surgeries are performed, most can pass in society.
However, the surgeries that M2Fs can undergo to feminize themselves are far more successful than those afforded to F2Ms (for masculinization).
Look at it this way, a M2F can undergo a plethora of surgeries and the end result is usually that she can pass as a genetic female, in intimate situations, unless scrutinized by a well trained eye. A F2M could NEVER pass as a genetic male, in intimate situations, because of the inferiority of the lower surgeries offered. Even an untrained eye could look at a F2M who has undergone lower surgery, and know he is not a genetic male (a phalloplasty is just -obviously- not going to pass, and a metoid still does not look male enough to allow passing).
I saw a thread earlier where M2Fs were discussing when to tell someone about the fact they're trans. Many replied that they wouldn't tell, or wouldn't tell unless it was serious. M2Fs have that advantage, later on, of passing -that- well. A F2M will always have to tell the moment sex (or nakedness) becomes part of the equation...because they aren't going to pass.
...and I'm rambling now. I suppose it's a trade off...F2Ms can pass more quickly, but not on an intimate level, whereas M2Fs have a more difficult time passing initially, but eventually can pass completely, naked or otherwise.
