Soldier fly larvae are the best! I was fortunate enough to have raised a huge stash of them in some old deer feed. My chickens and ducks nearly attacked me getting to them!I only use soldier larvae grown in the USA, never used mealworms. My girls love them & get a tablespoon or so between 9 chickens with their 3/4 scratch almost daily. They are penned, so it's their main source of animal protein.
I also get them live crickets from the bait store Once in awhile. Same reaction!