The problem is one has a sensitive system and has loose stools. It wouldn't be so bad, but he doesn't always get himself very clean. (I'm trying to be as tactful as possible.) I like feeding a premium cat food and have tried a couple, but it takes about 6 months to phase it in. We're trying a sensitive stomach one right now; they like the size, but I haven't seen any improvement.
I follow around one of my cats with "diaper wipes" trying to clean him, so any suggestions are very much appreciated.