Quote (Lensherr @ Nov 26 2014 12:36pm)
depending on which of the two is considered the best...
Well, it's pretty much up to you.
With ES you can certainly tank more, so long as you're 90+% ES.
With Vita, you can acquire more damage and even achieve Max Block if you wish.
Personally I prefer to use a vita blizzer because I'm lazy and don't like switching out cold gcs for light to achieve higher ES %.
I provided some guides for reference.
Hope this helps!