I would go with T/C for a standard chambering or Foxridge for a non standard. From my experience with 15-20 factory and 1 foxridge barrel the only one I had that would not shoot great is a 30-30. I have heard many complaints about he factory 223 and put off buying any for a long time. I know have two, a 14" and 23" and they both easily shoot sub MOA without much load tinkering.
Now I am a shoot and hunter and not a competition shooter, so MOA on the calibers that should be and 1 1/2-2 MOA on what is considered less accurate calibers is good for me. Because of that I cannot justify the added cost for the customer makers like SSK, Bullberry, etc.