for me, it's doesn't really matter if it is transsexual or transgender. Both makes sense if you look into the word and, at the same time both do not make sense if you look into the word.
Transgender:
Good --> It makes more of a connotation that one goes from one gender to another during transition
Bad --> It may connotate that you were that one gender and then made a switch. To many of us, we felt the other gender for a very long time
Transsexual:
Good --> It is the official medical term to describe us who feel that we are in the wrong gender and are taking steps to correct that.
Bad --> It connotates a sexual objectification such as Heterosexual=Different sex gender arousal, Homosexual = Same sex gender arousal, Transsexual = Crossing genders sex gender arousal.
In all honesty both labels are correct and incorrect. Where people mess up is when they judge one person for using a different label than what another person uses. You can run into issues of "superiority" when one starts judging basing on labels. I've read a very interesting set of blogs where one girl is dead set against the word "transgender." In my opinion, she lost her audience because all I saw was "complain, complain, complain" rather than her explanations of why she chose one label over the other. Likewise, the same is true for anyone who is dead set against the word "transsexual."
It really is a silly topic to be so upset about.
For me...if I had to pick a label it would be: female. If someone needs me to be more specific (like at an airport or something or at a rally or an activist gathering), I say: Transgender.
But really, to each their own. I just walk away from people who become ridiculous with labels.