Just my experience with it, been doing it since 2005. Casein free is a lot harder for me than gluten free. I'm also egg free and corn syrup free, although I admit I cheat a little on that one.
I only use Rice Drink. I get the enriched one that has calcium in it. I use Earth Balance for a margarine substitute. I do use some dairy products, just not cow's milk. For example, water buffalo yogurt is very good. I try to get it on sale because it is expensive.
10 years, many tests, 3 gi doctors, Pentasa 1000mg 3x day
diovan, simvastatin and now trying good ol' zoloft