I have been feeding FF since 2015.. no problems and back then it cut my feed costs by at least 1/3.. maybe 1/2 if you count waste.. Hard to tell now since chicken math is including subtraction every other week...They are in the poultry yards which still has grass/brushes/ bugs ...also and get meat/garden scraps so it is not all they eat.. in the summer I ferment a day or 2.. longer in the winter.. Have three 5 g buckets going right now.. go through 1 to 1 1/2 buckets a day depending on the weather... 7 turkeys and 60+ chickens of various ages .. I use this method w/milled feed https://tikktok.wordpress.com/2014/04/13/fermented-feed-faq/ .My peas and turkeys are spoiled... Chickens and ducks get the "leavings", and they have a choice to eat them or go hungry.