I wanted to add my two cents- that I think that it might be more possible to actually take stem cells and cells from a Transguy, biologically engineer them to "grow" genitalia, and then transplant them than it would be to clone another man's genitalia and then have them transplanted to someone else. As stated before, with any transplant, you need to worry about tissue/blood type, rejections, etc. But if it were to be biologically engineered from your own cells it would work- possibly even be able to produce sperm- but we are looking WAY into the future here. I don't think it will happen for a long time because Stem Cell Research is being focused elsewhere and to be honest I really don't mind, because I much rather give someone the ability to walk than have a penis and even functioning testicles.