I've got a 16" Fix .308 with a GM barrel. I haven't been able to get it to shoot absolute bugholes yet, but I'm not entirely convinced it isn't me in one way or another.
I recently sent an e-mail to Q asking some questions, two of which will probably interest you guys here. Spoiler alert, they didn't REALLY tell me anything.
I want to do a 16.5"proof .308 with a 1/8 twist. So,I asked if I could buy a barrel extension. They said no, they wouldn't sell me one, but that they are in the works and will be available in the future. No time estimate was given.
I asked if they had a favorite pet-load for their 16" 308. They said that it all depended on what application they were doing, but suggested I check out offerings from Hornady or Federal.....gee, thanks a bunch, I never would've thought of that.
I really love my Fix, it is just THE SHIT as a practical rifle. Which is primarily where I play. I shoot out of vehicles, I hunt elk/deer/antelope in the fall, coyotes in the winter, bear in the spring, prarie dogs in the summer. Practical rifle is just the ticket for me, so the fact that I'm stacking two, then throwing one out 3/4-1" at 100yds is not earth shattering for me, I'm not a match shooter. That being said, little teeny tiny groups makes me happy, so hopefully I can figure it out.