I have recently started thinking about this too. I am not all that happy with the food I have Bella on right now (Eagle Pack Giant Breed Puppy). I have done some research, including requesting from Diamond (manufacturer) a more complete list of totals. I read on a forum that it was a medium quality food. That it's better than anything you can get at the grocery store or Petsmart, but that it still doesn't compare to the premium foods like Wellness, Timerwolf, etc. His reasoning (he has his own dog nutrition site) was that the quality of ingredients they put in aren't as good, even though they're the same as what you'll find in premium grade. THe other thing I noticed is that it doesn't have any prebiotics/probiotics. I still know of a lot of people who have had great success with it, so I think I'm going to try it becuase the life of a single Mom doen't allow for much "premium" anything!