I do a lot of intra-CA, a lot of OAK to PSP, BUR, SAN, almost always on WN. I do prefer being able to pay extra for guaranteed extra legroom or F, but I rarely check bags and for short flights WN's frequency is a major benefit. Another big issue is being able to use BUR over LAX. I rarely use LAX now unless I'm connecting. I don't fly WN much out of state, and almost never east of PHX, but no way I'd go for status on another airline if it meant moving over my California in-state flights.