A legal defense fund can be a good thing if you trust the group to have the $$$ to back your case. It looks like there is currently $100K in the armed citizen's network's foundation for attorneys' fees.
On a side note we homeschooled our daughter, who is now in college, and we belonged to a homeschoolers' legal defense group (HSLDA). Cost us $100 a year and was worth the peace of mind to have attorneys on the other end of a telephone.
It might be nice to both have a firearms/2nd amendment attorney business card in my wallet and a group to provide $10k-50k upfront for attorneys fees while sitting in jail for a justifiable homicide (yes, self defense is still a "homicide"). At $85 a year it's like 3 or 4 boxes of ammo and range fees for one hour of practice.