It's really not good food. If you only have access to petsmart or petco, blue buffalo and natural balance are the best you will find there. If you have independent food stores in your area, the best you can get for your dog is innova, canidae or solid gold. For Innova and Canidae, their all lifestage formula is the best for large breed puppies, for solid gold I'm not sure though.
Canidae is the cheapest, it's $35 a bag, but you will need to feed much less of it, so the bag should last you much longer than a bag of authority.