Is there anything wrong with a MIM gas key on a BCG? I've read some complaints of cracked MIM gas keys where they were staked -- particularly on LMT and PSA full auto/M16 BCGs. I guess the circular MIM mark is between the two rivets/fasteners, to distinguish it from a forged gas key (with no mark). I have a PSA M16 BCG that has a MIM gas key that looks fine. Should I be worried?