damn, only one? guess sight,
because i think its awesome without feel, so you could like get shot, and instead of feeling pain, you could fight back
and also, many things are still the same with sight, you can know where your walking, without the worry of a random car hitting you.... but you wont know if there is a car behind you if you cant hear XD
also, you dont need the rumble feature on the video games, or the sounds, those are just to add to the game, as long as you can play it, and some games have subtitles for conversations and the such,
along with that, you could always learn sign language, or if your too lazy, write on a piece of paper
but nothing, nothing could be more useful than sight on the 4M................and the occasional pr0n site o.o'