You can consider this for what it's worth.
I recently emailed the NRA, the G.O.A. (twice), The Second Amendment Sisters, Florida Sport Shooting Association, The United Sportsman of Florida and The Second Amendment Coalition of Florida regarding a petition I started for the restoration of the right to open carry in Florida which can be viewed and signed at www.flopencarry.com
The ONLY institution that replied was the NRA stating they support both open carry and concealed carry and that they would forward the links I sent them to their florida lobbyists. From the others...nothing.
Strong testimony IMO.
Good thing too as I was just about to join the USF, had printed out the application and everything, that will not be happening now.
I am now also very happy to be a member of the NRA, having joined for five years several months prior to creating the petition and emailing them. Had they not replied, I would have let my membership lapse and instead of my small, random donations to their legislation dept. they would have got nothing from me. Instead, their personal reply to me was worth much more than they know. Guess you could say I'm a fanboy for life now and will be upping my membership to life member. I have also seen links to articles and interviews regarding the push for open carry in both Florida and Texas scroll across the bottom of the NRA's website.
I do not know if the other associations are offshoots of the NRA or not, they very well could be in order to make it look as though they aren't the only group in the world with a dedication to the second amendment and guns in general. I guess that would be hard to prove or disprove.
I would let this be food for thought before joining any organization, we join organizations in the hopes that they feel and think as we do, and are seeking the same goals and have the same agenda.
One way to determine if one is for you then, is to do as I have done...write them. No reply? Then why would you want to give them your money and proudly display that you're affiliated with them? If they don't have the time for you, why should you make time for them?