Sarah Jones answers:

Most dogs will thrive on most foods. No one food is right for all. There is no real information available for free on the net comparing how healthy dogs are on different diets. Part of the reason you are confused is that you are being given very little objective information. All the stuff you read on Blue Buffalo is based on its ingredients. Nothing, nothing on the nutrition that is in. The exact ratios of the ingredients and how they are processed have an enormous effect on what nutrients are available.

If your dog is doing well on what you are feeding it, stick to it. In reading through things here, how many times have seen people asking about why their dog has diarrhea after a food change?