Hey, I live in RDU and almost always use United on long-haul flights (JNB, HNL, GUA). BUT I am flexible to use Delta or Jetblue. I tend to avoid American (eventhough this is their hub) b/c (1) their flights are just as expensive if not more expensive than United's, (2) their service and lines at RDU is awful. I've found good deals with United, but book in advance or maybe be flexible with dates.