We'll I wanted premium for my baby, but he didn't like the premium food, and hasn't done well on some brands, so we use Royal Canin, and Joey doing really well on it, and has super shinny hair, but more importantly he'll eat it. If the breeder had your little girl on it, I wouldn't change for the first month or so. I think adding too much variety the first 6 months makes them more prone to allergies. Food is a highly controversial topic, and I'm not sure there are that many facts out there right now, it's hard to separate the truth from the hype. I think this web site is helpful in sorting out the truth from the fiction.
The Dog Food Project - Myths about Dog Nutrition