Come on now... that surely depends on what you mean by "superior".
Fact: Whey will get in your system faster than a steak.
Fact: Casein will remain available in your system far longer than whey will.
i.e. Whey is superior to beef for rapid absorbsion.
And... Casein is superior to whey in preventing the onset of catabolism while sleeping (if taken before bed).
.
Whey or casein are not superior...
