My dogs have been fed Challenge Salmon and Potato for a number of years and have always done well on it, so on the principle of "if it 'aint broke, don't fix it" they will continue with it. They always clear their bowls, will eat it dry and they look well on it. It isn't bulked out with cereal and doesn't contain pea flour which has caused allergy issues for my dogs in the past.
Delivery is always prompt and the price is reasonable.
My only minor criticism would be that the pieces are now larger than they used to be and are more difficult for my smaller dogs to manage.