if you lock-tight and stake the key properly --that about as "solid" as you can get without welding.
i know of people running the BCGs with JUST the lock-tight. no staking at all-- as far as i know the screws ain't backed up yet-- i figure they want to be able to take the BCG apart without having to grind/cut anything.
i lock-tight and stake mine pretty hard-- though i am one of them guys that is prone to over do stuff.
no staking ain't a big deal --nice if it is /no biggy if it ain't--