Now that some of the "better" cat foods like Science Diet, Iams etc. are more readily available at discount stores and don't cost as much as buying them from the vet, we are wondering if we should switch from Purina to one of the more expensive brands. Are these foods really that much better for cats and worth the money? If they are, which ones do people prefer? We have also noticed that Purina is making a more expensive dry cat food and wonder if it is as good as the "better" cat foods. Any advise any of you could give would be most appreciated. Thanks. In peace, Hannah