I still have some goose fat from Christmas in the freezer RM. I regard that and duck fat as the best ever cooking fat.
When I was getting duck carcases from Coombe Farm to go in the stock pot I was able to save the duck fat which rendered off from those. Sadly, their deliveries were unreliable and I decided to look for a more local supplier of broth/stock pot ingredients where I can get chicken carcases but not duck. OH does not like duck to eat, so it is a rare treat for me.