I agree that the emails are annoying, but I like their magazine, there
is value in the Defense Shield, which is now part of the membership, you can get various training books and DVDs at a discount and their forums aren't bad either.
I just renewed a few months ago. I just have the emails filtered to go to their own folder, so they don't bother me.
From an attorney/defense standpoint, I prefer the Armed Citizens Legal Defense Network.
http://www.armedcitizensnetwork.org/home