Glad to hear the Omega sounds nice. Mine is still in jail so I'm running a YHM ULT. I wouldn't expect the brake to do much on 5.56, partly because the .30 cal hole is going to let a lot of gas out the front. I plan on running the flat cap for length and noise.
I am running an SLR gas block and couldn't be happier. Very quality; easy to adjust but no way in hell is it going to move on you. I see no reason to consider anything else.
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