Do you prefer a Two-Face with or without an alternate personality?

Not many Batman villains have an alter ego in a similar way to Bruce. Harvey being a good man, and Two-Face being evil and in charge is a good source of conflict.

His name is Two-Face with half his face burnt off this creates a clear dicothomy between two personalities. I dont think the name or half burnt face qould have the same effect if he didnt have a split personality.