I have done straight grind, added suet, added pork and added beef. I prefer some added fat. Ex neighbor that was a butcher claimed that all suet is not the same. If you have a source he said to ask for prime rib suet. Pork is good but I have read that pork fat will not last as long as beef in the freezer. The last few years I have used either cross rib roasts or brisket, both beef. My hunting partners wife has been trying to get him to add something for years. Her and I went to the Cash n Carry in Clarkston this year and bought an amazing looking 23# brisket. She loved the final product after being ground with 100 lbs. of elk meat.