If Sara is a woman in a man's body then I'm a god trapped in a mortal's body.
I can tell you right now, there's absolutely no way you can argue that I'm wrong without admitting that Sara is just a man dressed as a woman. Just because you can think like a woman and act like a woman doesn't make you a woman. If you're born a man, then like it or not, you're a man. Just like, if you're born white, then no matter how black you think you are, you're still white. You can dye your hair purple but that doesn't change the fact it's still dyed.
Furthermore, if a man were turned into a woman (I don't care how; magic, genetics, whatever, so long as the person is completely physically changed-as in, can have babies and the full nine yards). Then that man is now a woman, NOT a man trapped in a woman's body. In this case, you really can judge a book by it's cover. I wont lie though. If I were turned into a woman, I wouldn't change my tastes just because I was changed physically. We are who we are based on our experiences, yes but we're also who we are physically. A person who believes they're a woman with the body of a man is just that; a man who thinks he is a woman.
People who find transvestites interesting will possibly like this manga because it's one of the rare few written about a transvestite. However, you'll probably find stories about transvestites written by real transvestites more interesting.
People who were looking for a normal person suddenly thrust into an identity crisis over some dramatic physical transformation will not like this manga. In fact, this manga even fails at creating an interesting love story.