Transporters still give me a philosophical headache, so I think I'm glad they aren't real. (yet?)
If a subject steps on a transporter platform at point A, gets taken apart and has the pattern recorded, then that pattern is somehow communicated to a platform at point B, which then builds from local material using that pattern, and a person steps off the platform, is that the original subject? Or did the original subject DIE, and now this is an exact duplicate, but not the same person? And if it IS the original subject, how would it work out if you just recorded the pattern, and left an intact original, but still assembled a person on the other end? And let's not even get into what happens to the soul (souls?), if there is such a thing.
There's a book on the metaphysics of Trek that talks about the concept of the Closest Continuer - basically the idea is that whatever is closest to being what you are now in a second from now IS you. So if I cut off your arm, the you-without-arm continues to be you, while the arm is not-you. Or, applied to transporters, the person at point B IS the original person because they are the closest continuer of that person. Interesting, but I don't buy it well enough to be testing it with myself any time soon.
Sorry to ramble on, but I find this subject ... fascinating.