i actually have and do and like to use merrick, my dogs and cat like their foods (both dry and wet) and their families rendering plant they dont use the "left over" meats in their pet food plant, however they do use the beef tendons from their rendering plant to make their bullysticks and their rendering plant is also where they get some of their other "leftovers" for chews (ie pig ears, hooves, knuckle bones ect). (while some still and always will belive they do use scrap meat in their food...)
as for "safe" none of their graines are imported so yes, it is "safe and NOT on the recall list, nor should it ever be thanks to the fact they dont use imported grains.
it is one of the few dry/wet foods i still trust.
our cat LOVES the canned food. the dogs only like the grammies pot pie in the dry and about 4 of the many wet foods.