Each type of protein contains a different amino profile. Some proteins such as egg album and milk casiente provide sustained amino release; conversly, whey is digested very quickly. Unless you're a woman, soy is a terrible source of protein. Soy blocks estrogen receptors causing a rise of estrogen levels in the body. Unless your going for the bitch tit look i'de strongly advise against supplementing with soy products.
just my .02