Here's my take on the question:
NRA - as Nicole says, they are the 800# gorilla that scares Congress and that is a good thing. When push comes to shove, they are too willing to compromise the rights of those of us who believe in owning guns for self-defense, in favor of protecting bullseye/hunter gun owners.
SAF - top notch court cases (e.g. Heller, etc.) in Federal Court to make substantive changes in the anti-gun laws nationally.
Comm2A - MA org bringing Federal cases forward to make substantive changes in the MA anti-gun laws. Work with SAF in this mission. [They are a parallel org to GOAL, the charters of both are different from each other and attack the problem from different directions.]
GOAL - charter is strictly to work with legislation (NOT litigation, see Comm2A for that) in trying to change gun laws. Realize that we do not have enough elected friends in the state house or enough members to have the clout to truly accomplish this. GOAL is very good at PREVENTING more laws from passing that would further erode what few gun "rights" we have in MA.
My Wife and I are life members of NRA, GOAL and SAF plus monthly contributors to Comm2A!