Barring its issues with ftf fte chronic slamfires (there are still samples hitting shelves doing it) an issue a lot of people have are the basic ergonomics. The right side selector is inline with the trigger and trigger finger. There is the very heavy weight for what it is, the scar17 some larue obr and a few other brands chambered in 308 actually weigh less than a acr in 556.
Its a gun that little real engineering or thought beyound "lets make it look cool" went into it.
I think it went something like "hot damn a contract!! lets whip up something futuristic looking and get it to the contract testing!! " then after it got passed over they had to do something with it to recoup costs so off to gunstores it went.
If you do get a problem sample they will make it right. Eventually it will run justfine if your unlucky to get a flawed one.
"Gun control: The theory that a woman found dead in an alley, raped and strangled with her panty hose, is somehow morally superior to a woman explaining to police how her attacker got that fatal bullet wound." — L. Neil Smith