Buy one of Constructor's barrels, a super bolt, and never look back. There are 1000s of post of the net proving the accuracy of his barrels and his service is top notch. He's a great guy to chat with about any questions you may have as well.
That certainly wasn't my experience. To be fair though, mine wasn't a 6.8 barrel. He may be good to go on 6.8 stuff but I wouldn't recommend any sort of wildcat chambering from him.
