If the same rules apply to these heads as tom heads, then the Emperor X would be more focused than the Focus-X.
That being said, a helluva lot of people (but not all) have gotten Emp-X's and not been able to tune them all too effectively at all. LeeLovesSabian is obviously not a part of this group.
I think that you should go for the Focus-X because it's the single ply, and I can't really think of a good, not EQ'd two ply snare head that I have actually heard myself.