This is something that, like any sexual experience, depends on you, and the other people involved, and of course the circumstances.
I actually just had a threesome with some friends of mine a few weeks ago who are a couple (I’m gay). It was really, really fun and felt great. So much physical and visual stimulation.
I had a threesome once after I first came out that was just uncomfortable, akward, boring and yucky.
I would not reccomend going through life with the specific goal of trying to make this happen. If you want to try it, just keep that in mind and be open for the opportunity. I’m not saying don’t take initiative to organize it, but honestly, I don’t think it’s something that totally needs to happen in life.