I got my AR-Stoner upper over the summer. Since then I've put over 200 rounds through it. It is on a factory RRA lower with a 2-stage trigger and has a 3 x 9 Leupold mounted on it.
Originally it would not feed Remington ammo, but it fed Hornady and Winchester just fine. I added a SilencerCo muzzle brake and a Hybrid Suppressor. The additional gas must help, because it will run Remington ammo with the can mounted. I've had good results with AR-Stoner magazines and 10-round 6.5 Grendel magazines (with an added notch).
Accuracy with the can is 2-3 inch groups at 200 yards (when I do my part) and it shoots Remington and Hornady ammo to almost the same POI. The Hybrid gives the rifle a different recoil profile, it seems to push straight back. It is also comfortable to shoot without hearing protection.
Overall I'm impressed. It is accurate and the round hammers deer.