I have a RRA Entry Operator 2, and love it so far. My only complaint is that the hand guard is only a quad rail setup on the front end of the hand rail, and the bottom rail is only long enough for one item. I'm wanting to replace it with a different one that has quad rails all the way back, so I can move my grip in closer, and install a bipod on the front of that rail. The handguard is a free floating aluminum that has a barrel nut, like the one on the half quad rails currently on. RRA recommends having a gunsmith make the switch, but I was wondering how difficult it is for a black rifle newbie.