I am interested in a complete RRA flat top upper with a 16" bbl that is chrome-lined. It is my understanding that only the m4 profile bbl is chrome-lined from RRA. My diggin leads me to believe that the entry upper is my only choice at about $200 more than the car A4 upper, and it has a muzz brake on it (YUKKK). Yet on RRA website they list c-lined 16" bbls at only $30 more than c-moly bbls. Am I missing something here? Would you build aRRA flat top upper with a c-lined bbl? I really don't want to have a bbl with a muzz brake on it (if at all avoidable). That said, hbar would be my first pref then m4 profile. I have seen the faux flash hider pressed over the bbl, OK I guess if that was the only option.