...Maybe it's somewhat insulting to trans people, but I just find something extremely kinky about ladyboys...
It can be, I think it depends on the situation and the type of ladyboy. Not all ladyboys hate their penises, but for those that do, tread lightly.
A very fem TG once asked me why I liked TGs and I had a very hard time answering because I didn't want to tell the truth and hurt her feelings by saying it mostly had to with kinky sex. This particular newhalf wanted desperately to be a full woman and was saving up for the operation.
I stammered and came up with something along the lines of since TGs try harder they are more feminine, but I really don't believe that to be true in all cases. Sometimes it is true, more often it isn't.
It was obvious that my improvised response was bullshit and I could see how she was disappointed in how I responded. She knew the answer before she asked the question because she said something that equated to, "Thank you for being a lair."
That is an answer one should probably keep in their back pocket if they are developing a friendship with that type of TG, because it will probably come up.