There's alot of great barrel makers out there. I don't think proof is the best. But they are pretty great.
I have two buddies that have the same proof prefits in the same caliber. We can all swap our match ammo in the others gun and it shoots within a tenth or 2 all the way out to 1000 yards. Granted we are literally using the exact same brass, components and powder. Other then different lots of the same stuff, it's all the same.