I have a 6 bra, fuzion aw cut action, very similar to your 737. Tried aw with hrd kits, arc with pva kits, accurate aics with primal kits and mdt br mags. Never could get the arc/aw to feed worth a crap. The accurate with a lil feed lip tuning are gtg. The mdt br with a lil feed lip tuning have arguably been the best. I know not completely apples to apples but my experience. Mag latch height has to be high to keep aw mags pushed up high for the low case head presentation of aw's double stack double feed format. So a chassis with adj latch, or a bottom metal with available longer latches is the route to go if you desire aw mags.