I've tried different brands of expensive high end dog food and I have never seen my dog respond so positively to anything except the prey model raw diet. His coat has more shine, he has more energy, and he hasn't been itching for no apparent reason anymore.
The diet is raw muscle meat, organ meat, and bones. Again the bones especially must be raw. Apparently dogs don't need fruits and vegetables like humans and are more suited to a an animal based diet like their wild ancestors.