At this moment, for me, butter seems to beat suet by far.
When I tried to witch completely to suet I did not realize how hard it is to digest because I was eating it with high meats and when I ate it with fresh muscle meats... ohh the pain. I haven't had indigestion for a looong time, even when overeating junk foods.
I will only try suet in small quantities or maybe experiment with a gradual increase.
I would love to not relay on butter so much because it's sometimes hard to find raw.