I am getting a Dobie pup and I have to feed him a premium large breed formula for his gaurantee for the rest of his life.What is a good premium dog food.The breeder uses Nutro but someone else I talked to said the nutro wasnt a real premium dog food.That I should use Wellness or something else but I cant remember what it was called.I have to keep every receipt of where I buy dog food so I need to know what kind to buy.Any suggestions.Cost isnt really a factor, but I do want the best for my new pup or as close as I can get.