I have quite a variety of aftermarket barrels and I can't say any of them are not a big improvement over a factory tube. With that said, one of my absolute most accurate barrels is a Hart 1-12 twist on my 40X chambered in 220 Swift. I believe Hart barrels still holds the records for most matches won in Bench rest comp. Just my 2 cents. I am sure this will turn into a Dodge, Ford, Chevy debate.