I’ll throw in my experience with a Mega barrel. I built a MATEN last year and decided to go with a 16"Mega barrel. They guarantee sub MOA so I was expecting that but it far exceeded what I thought I was going to get for precision. I consistently shoot sub .5 MOA with this rifle. Most 100yd groups are .3". I can outshoot a lot of bolt guns and I did not expect that out of this barrel.
Hell, a couple weeks ago I was shooting on a buddies land and we were hitting cattails at 200 yards…this is a fantastic barrel. I’m bringing this up because it was such a surprise for me and I don’t hear anyone ever mention Mega barrels for precision rifles…I’m convinced they need to be brought into the discussion now.
Good luck and enjoy building your rifle!