fire es sorcy question.

[Beoron]

So I am making a 200 fcr fire sorcy and trying to decide between es or full vit and I dunno hydra maybe. I see a lot of people say "Boo on es, you won't have enough mana" My question is though, even if the 200 fcr sorcy can't get huge mana don't they usually end up with more mana than life? If so wouldn't that make going es better than full vit? Also, with a full vit build how the heck can I spam tons and tons of fireballs? Am I just supposed to use bolt? I am just curious as I don't really know for sure. Thoughts?

And sorry I know thisis an oft discussed topic, but no one seemed to address these specific points.