I identify as pansexual. Genitals and gender are irrelevant.
HOWEVER.
I have a lot more luck with girls. Gay cisgender men very rarely take my seriously because of my genitals (that is my experience, I'm not sayin' it's true across the board or anything). My ex is a MtF. When we first started dating, I knew her "as a man." She did come out to me fairly soon after we started dating, and then started her transition (socially; she wasn't on hormones or anything yet). But somehow she always had that feel of a woman. She was incredibly gentle "for a man." Now I know gender roles are a load of hooey, but something about her was just feminine in a way that it was no surprise when she told me she was female-identified...
So. -I- don't have a preference when it comes to genitals/gender, but other people do. I have much more luck with women. Even straight women seem to be much more okay with my body than gay men. Because of my bad experiences with bisexual and homosexual men, I have a hard time trusting them. I've actually gained trust issues with men. I've had even trans men tell me I wasn't good enough for them because I don't have a penis. That right there has messed me up in the head.