Out to what distances are their 3 Gun matches out of curiosity?
In USPSA 3 Gun competitions roughly 25% of targets are in the 200-300Y range and another 10% are over 300Y.
What is the problem with someone wanting to buy something better than Norinco or NEA or something designed for the task at hand?
Maybe they can afford to buy both a better rifle and lots of practice ammo.
It goes back to the title of the thread which is The best out of the box AR-15 for 3 Gun.
300 metres isn't an issue for a bone stock AR. There really is no need for match grade parts.