Ah, did they finally update the gender options? I remember someone posted a news article about how they were testing it out with a small percentage of their current user base.
I was on there when it was just male and female. For a while I identified as a lesbian and made the restrictions that I prefer bisexual women and had a short anecdote in my profile explaining my gender identity and who I was interested in as a result. I had some luck with it, in that I got a lot of conversations out of it. But it always felt very false to me, to have to identify that way.
I switched it to male and straight and still got a few messages due to tagging things like transgender, queer, and ftm in my profile. But I also got a lot of views from people I was absolutely not interested in.
I'm from the greater Washington, DC area so there is no shortage of LGBTQA+ people around. I mostly felt like no matter how I chose to identify with the available options, I was not being 100% truthful, which is an issue for me. I may try it out again if they've altered the gender options. I'd definitely feel a lot better having it immediately displayed instead of buried in my profile.
Don't know if you use Tumblr at all, but I also wrote a little blurb about myself and posted it on a few trans blogs on there. Got some new followers, found some new blogs to follow, and had a lot of good conversations as a result. IMO, 1000x better than a traditional online dating experience.