I was reading a similar post on another board and someone made a great analogy

Eating grocery store dog food is like a human eating McDonalds every day. It will taste good, you will live on it, but it is unhealthy.

That said, I believe that people should buy the best dog food they can afford. If it is Purina, so be it.

I used to feed solid gold, now feed Innova. My dogs also get Solid Gold Tripe 2 tablespoons once a day.