I have a three and half month Great Pyreness/Golden Retriver mix. The people I got her from fed just regular Wal-mart brand dog food. I switched to Puppy Chow.Recently went to Pet Smart and one of the workers said I should switch to a brand named MAX. Problem is she doesn't like it.Should I go back to Puppy Chow,or is there another brand out there that is good for puppies that won't cost me a arm & leg? I don't mind spending $15 -$20 for twenty lbs. of food. Suggestions in this price range? I want what's best for her.