IMO, GOA is a total waste of money. I don't think anyone outside the choir takes them at all seriously.
NRA membership is not a waste of money unless you think the money goes to protect the second amendment directly. If you realize you are buying a magazine subscription and subsidizing highpower shoots along with educational programs and ranges than you are good to go.
NRA-ILA and NRA-PVF both seem like decent places to send your money.
SAF seems to be more bang for the buck to me. SAF does little lobbying.
Groups like JPFO and even Pink Pistols come from an angle the NRA lobbying members can't.
NRA gets by far the most money out of all the groups. In excess of 60 million dollars a year in membership dues. None of it goes to lobbying or court battles.