It's legit. I signed up and got my membership card in the mail a few days ago. Only thing is I don't think you get the free magazine subscription. I went and subscribed to Shooting Illustrated anyhow cause it seemed like a cool magazine.
With the membership they send a survey they ask you to fill out. With that I did however have a chance to extend my membership for a reduced rate, and I decided since I got the free year, I could afford to pay $25 for another year. At that time I did get to choose a magazine subscription. But I'm not sure if I would have been able to choose the subscription without extending, so maybe you'll get it just with the free year.