I flew WN intra-California for years and enjoyed the benefits a lot. Here there wasn't any contest in terms of perks -- Southwest was the best for this kind of flying. Nowadays I know people who are into Virgin America or JetBlue for some trips but for my colleagues that still travel in-state they all have kept to WN.

As one of those tall people (about 6'4") I also like to be on a 737 instead of an RJ or EMB. The mainline equipment is more comfortable for me and I also like to be able to stand up without banging my head on the ceiling. Yes, the 170/190's are actually almost 737-equivalent for me and the 700/900's are not at all bad. But I avoid the 100/200 CRs like vampires avoid sunlight. So for me it makes sense to travel with an all-737 airline (AirTran excepted) instead of worrying about finding myself on a 100/200 or something worse.

Of course much of this could be avoided for all if airlines simply restored the standard pitch in coach to 34".