Oh, it would leave a lot of sensation. Bad sensation. Apparently a neo-vagina constructed from colon tissue feels like you're pooping if you... well. Not to mention that the procedure is infinitely more risky and complicated if it implies that sort of tissue.
Yeah no, in all practical terms, what you're saying is pretty much impossible. All current techniques, both for creating a penis (and those are even more limited) and for creating a vagina, base themselves mainly on the existing sexual organs. If you use the materials for one sexual organ and you want the other one too, then you need to be creative. THEORETICALLY I guess it would be possible to keep the penis and construct underneath it, where the scrotum was, a vaginal cavity. But without the penis's material, it would need to be sewn on both ends, which I'm pretty sure vastly complicates healing and care, AND you'd need to take the skin from elsewhere. The safest available option is probably to take leg skin. As long as you don't mind the Frankenstein scar, it should have decent results. There's also artificial skin cultivation, but that's at best experimental.
I GUESS a somewhat alternate option would be to have a normal SRS but to have the surgeon especially make you an extra-large clitoris... the way FTMs end up after a while on testosterone. There's your "penis". However the same way it probably takes an FTM a lot of imagination to forget about how it really is and imagine it as a penis, it won't be exactly satisfying to you. Not to mention that I can't help but think that essentially making oneself an artificial hermaphrodite just must feel weird to most if not all gender identities of the vast spectrum.
What you can do, however, is talk about this with someone competent to understand it further and be more enlightened to take a decision.