It's amazing how vehement some people can get about cat food. Much like humans, every cat is different. Some can thrive on "junk food" (it's up to each purr-ent's opinion what constitutes junk food) and others need special food, whatever that may be. As far as the controversy about synthetic additives like antioxidants goes, they are used in human food with very little controversy. My one concern is some of the synthetic dyes. I had a foster that was ferociously allergic to a dye in some cat food. As soon as I changed foods, her digestive problem cleared up.

Anyway, if the cats like the food and aren't sickened by it, stick with what you're doing.