Erick great thread! It is disappointing to hear that your barrel needed replacement at 10,000 rounds. I wouldnt expect that from a CHF chrome lined barrel. I am at just under 20,000 rounds through my KAC with barely a perceptible opening up of my groups which were very good to start. I have a good friend who shoot primarily steel case/bimetal and he got just under 20k out of his LMT SBR before his barrel was done. The only reason I dont shoot steel case as much is that much of it, even when marked is not loaded to 5.56, it is mostly .223 and often there is a fairly decent variation in loadings. If shooting steel case gets someone shooting more then it is more than worth it.
BTW using brass case ammo isnt always a guarantee of good ammo. In late Nov I had a double charged round blow up in one of my ARs destroying the upper receiver, bolt, firing pin, and a magazine. This was not a reload, it was factory new from a major manufacturer.