A lot of people, including me, have been making fun of this on other forums, because at first glance, it seems to be a marketing gimmick. M.A.'s assessment is helpful, but.... When asked, I say that JC is an "alley cat", because he looks like an overlong, oversized domestic shorthair with a narrow face and a hairy belly. In fact, his mother was a white Oriental Shorthair (basically a Siamese without the mask and dark legs), and his purported father was a Norwegian Forest Cat (the closest thing to a Maine Coon here in Europe). RC doesn't agree with him - he's had the Kitten, Fit, Light,Indoor, Hair & Skin, & Sensitive formulas, and developed severe dandruff every time , but if I were to feed it, what would I do? Mix RC "Siamese" with RC "Maine Coon"? I have heard, on other forums, of many Persians who have developed allergy and/or urinary tract problems after being given the Persian formula. Another problem that has come to my attention is that some cats given RC don't seem to develop struvite stones, but have trouble with oxalate stones. So I'm a bit sceptical still. I don't want to imply that I consider RC an inferior food - it is far better than most supermarket brands, and invented dry cat food, but it doesn't agree with many cats, and I would like to see the problem of grain allergies and oxalate stones addressed before the company adds more specialties to its line.