I second MrBigAir. I commute and have 3 options but I almost always end up on NWA. The pilots and flight attendants are always fantastic and very accommodating. I also have to say that I personally find NWA's policy of making you actually show up at the counter is the most fair way to do it. Nothing worse than running across 3 terminals after a long trip, thinking you're the first one there, then finding out that some other offliner listed from the outstation and is ahead of you for the seat. First come first serve is the way to do it.

Thanks again and in advance to NWA!