I have found that the best way to use a peletized deer feed (to prevent molding)is to build a covered feeding trough. Make the roof high enough above the food to allow bucks with big racks to get to the food. The amount of food other critters eat is so little it doesn' t matter just make it high enough so pigs have trouble getting to it. As for what feed is good and what is bad. I look for a feed that has at least 15% protien. The most important time of the year to put feed out is Spring and Summer. The high protien makes a big difference. I have looked at the Purina and it has minerals that the cattle feed that I have been using does not. Other that that it is about the same thing. I put out about 2.5 tons a year on 3000 acres. The average B&C score of the bucks taken has increased 20pts in the last 2 years. I know I am long winded but I hope this helps.