I'm currently looking to get into 3 gun competition in the north ga area. Started looking into an "entry level" AR.... Price-wise , I have narrowed down to a stag, del-ton, or the bushmaster with the carbon fiber receiver. Any thoughts on the pros and cons of these? The other 2guns that will be completing my rig are a benelli super nova, and a colt mk iv combat commander. Also, any advise on gear set up and such, would be greatly appreciated.