I say run with 300 BLK and don't look back. Arguably far less finicky about "tuning" when going from suppressed to non-suppressed, and damn near hollywood quiet with a decent can. Mine has no adjustable gas block, a standard carbine buffer and spring, and it runs just fine either way. Of course, once you get with suppressed 300, there really is little reason to take the can off. Maybe to run supers for hog and coyote hunting, but you can run supers fine suppressed, its just a little less quiet.