User blog comment:Dragoon224/Changes Riot can make to LoL/@comment-78.30.161.215-20120812210612/@comment-4834593-20120812213802

Vayne: You really want to waste at spell vamp while life steal is a lot better?

Darius: Eh, sorry. But his Q has reduced effect, his W procs life steal, his E doesn't do anything, and if you let him ult more than once, you are already doing something wrong. Spell vamp doesn't matter on him, life steal is better.

No, this item is not for some AD carry or AD bruiser, it is for AD casters like Riven, Talon, etc, who deal mostly damage from abilities, and, this way, have no viable way to sustain themselves in team fights, except if an ally buys WotA.