Every additional NRA member causes the collective blood pressure of the Brady Campaign to go up by 0.01 mmHg.
If enough of us join, their heads will explode.
I'm considering developing a multiple personality disorder so I can be more than one member.
More seriously:
Some people say that the NRA is the largest pro gun rights organization, the most influential, the has the most actual impact on legislation. Therefore you should join the NRA.
Some people say that the NRA is more focused on short-term micro-wins than longer term objectives, and there are some important gun issues that they don't really address.
I say both are right. Join the NRA, AND join whatever other organization represents the niche issue that is most important to you.
PS - for the folks who are seriously worried that the NRA's accountants can't do math, and believe the NRA is losing money on their fund raising efforts: Please, take a deep breath, step back from the keyboard, and think for just a nanosecond before you start to type. Thank you very much.