There are several people here on the Forum who are real food nutrition experts, and I think they would say . . . Purina and Fancy Feast, while the cats might love them, are the lowest quality foods out there. The line goes, you can't buy anything good at a grocery store, Walmart, or Target.
I hope they pipe in, but the strong bias is on giving cats canned food instead of dry (to keep them hydrated, among other reasons). I get Murphy canned food from Trader Joe's, which has its own brand of food, is good nutritionally, and only costs 69 cents a can.
Holly and Murphy