Arm of carseat broke - DO NOT BUY

I read another review and it seems that I am not the only one who had this happen. The part of the carseat that comes over the child's head (the arm) came loose from the carseat on one side. When this happened, I was out running errands and forced to carry my child home in my older son's booster. I returned it to walmart where they were very hesitant to help because I had no box or receipt. They made me feel as if I were trying to rip them off when, in reality, manufacturers imply that a carseat should last a lifetime providing it is not in a wreck or mistreated. After escalating to the store manager I received a partial refund (he gave me $35)toward another carseat. What would have happened if we had been in a wreck? My child would have been thrown out.