I’m running a superlative adjustable gas block and Brownells light weight carrier. Standard Carbine buffer works fine, I had a silent recoil system in mine at first but it wouldn’t allow my bolt to travel far enough to lock open, not sure if it was a one off thing with my parts or what. Either way if you’re running an 18.5” barrel and rifle length gas system like me you don’t really need the adjustable gas block, mines just about full open anyway and you save a tiny bit of wheight and one less point of failure