Not all dogs do better on high quality foods. Poor Buddy - I hope he's better soon.

I have to admit though, I've heard of a lot of dogs that have had problems with Wellness products. Have you ever tried any of other premium foods? Canidae and California Natural (lamb) are both generally great for sensitive stomachs and the California Natural is also made specifically for dogs with allergies/skin conditions. Those are the only two brands Winston can eat without either stomach or skin problems, and I've heard the same from many other people.