Do a search with nea as the key word and three years as the time line, prepare to be amazed. The issues include but are not limited to
Broken bolts
broken cam pins
over sized holes
doubling when firing
loose barrel extensions
loose gas keys
unstaked gas keys
gas keys with angle grinder damage
rails out of square
burrs
rifles shipped with no BCG
cartooned flash hiders
ejection port covers that don't fit
over sized gas ports
barrel extension failures
charging handles that wouldn't clear back plates
uppers that are out of spec
lowers that are out of spec
bolt ford assists that fall off
Those are just the ones I remember