Short version: no real preference for cis men or trans men. Like pussy/ass about the same. But I have a cuckold fetish and get turned on by guys (especially if gay/bi) talking about fucking pussy (dm me if you're into this too).
Long version:
I've always known that I liked dicks/men, but I also knew I liked vaginas. The women they were attached to were a big turn off, though. So I rarely watched any pussy porn.
Until the day I found my first trans male video while watching porn with my bf (sadly, my ex now). He wasn't into it at all, but I thought it was amazing. After that, I pretty much watched nothing but ftm porn when I wasn't with my bf. I'd go as far as to say I had a fetish for trans men.
And since the bf and I were poly, I started looking for transmen right away. Found one who was a bottom and was chilly l comfortable using his pussy. As a bonus, he was into threesomes and thought my bf was hot.
Bf wasn't sure he'd be into it, but this guy was the tiniest, cutest little twink so it didn't take too much convincing.
When he gets here, the three of us chat for a bit, start making out, and then start giving him head. The taste could be better, but I still get rock hard, especially seeing that bf is too. Bf moves up to get blown, while I rub my dick on his pussy for a bit before sliding inside.
It honestly didn't feel better than anal to me, but it's still sex with a dude so it's great. He felt less tight than an ass, but the pressure was much more evenly spread on my dick. Also loved how wet he got.
I fuck him for a bit, then pull out so I can watch my bf his first pussy. Bf lets out a moan as soon as he's inside, then starts pounding the hell out of him. Less than 30 seconds later, he's moaning and cumming so hard that I think he's kidding. I find out how wrong I am when he pulls out and his load starts dripping. It's the hottest part of the encounter for me.
Bf lies down on the bed, mindblown. I kiss him, then move down to eat his load from the guy's hole. I'm edging myself while I lick and try to get him to cum. Takes a bit (and some helpful instruction), but eventually I hear him moan and feel the contractions. I cum on my hands, we clean up, and he goes home.
I ask the bf if he liked it, shit-eating grin on my face. He's a little bashful, but says that's the hardest he's ever come. Which is a huge turn on for me, since I have a cuckold fetish. And seeing him how hard he came makes it even hotter.
We hooked up with the same guy a few more times and eventually bf started dating another trans guy for a bit. One day he tells me that he thinks he might want to try to fuck a woman, surprised me a little, but I encourage him. He experiments for a while and comes to the conclusion that he's bisexual, but homoromantic.
We eventually broke up when he had to move back to his country (he won't do long distance relationships), but we still keep in touch. Might get back together after I'm done with college. But after those experiences, gay/bi guys who love pussy are definitely my biggest turn on.