I am considering trading my leupold Mark 4 for a upper it is dpms upper 16.1 m-4, 1/7, chromed lined, m-4 feedramps, chrge handle with pri big latch, complete bolt and carrier, arms#40 rear buis, m2 aimpoint with double battery caps,killflash, arms#68 mount with removeable riser, aimpoint quick...