L.W.
My son has been drinking soy milk since he turned one. He is allergic to cow's milk. Everything I have read indicates that soy milk is healthier then rice milk.
My advice is to just do what you feel is best for now and let later take care of itself. Last year all we heard was how everyone should be drinking soy...now, not so much.
My son is 5 and very healthy (except for the dairy allergy!). Follow your gut and don't feel guilty after you make your choice.
Good luck!