He can be. There were times with QPR (and that one game with England) where I was blown away, and you start thinking that he could develop into a monster of an attacking threat. But those instances are few and far between, and his decision-making on the whole is awful, and doesn't appear to be improving. I don't think that he's a player that you can rely upon to contribute positively more often than not...he's in the same spot as the Ben Arfas of the world, good for a highlight reel but less so for a team.
Like Mayuka (but 10x more expensive).