All points made above are good. The primary purpose of the 6 Creed was again for mag length restrictions. The 6mm battle is the same as the 6.5 battle between the 260, Creedmoor, and Lapua variants. They all do about the same, but the cases with the 30* shoulder have a few advantages.

The 243ai will get about 200fps more than the others due to increased case capacity, but the 40* shoulder is known to not feed as reliably.

As for barrel life most guys are swapping barrels at 1500rds in any of these variants for serious competition as they are seeing the lands wear done a few thousanths every 100rds through the barrel.

I shoot the plain old 243 with 105 AMAXs vice the 105Hybrid. With 41.3grs of H4350 I'm driving them to 3025fps and haven't adjusted my load in any way in 800rds. The Bergers seem to be a bit more jump sensitive.