Who would you rather have zack greinke or clayton kershaw?

I am trying to make a trade but he has both kershaw and greinke, Greinke's just coming back so I feel like he will get better and his one walk keeps him with a nice whip, if he continues to keep them low. Kershaw has been pretty consistent and thats about it...But the fact he was a high ranked player start of season makes me feel more comfortable with him. I am most concerned with a low era and whip more than wins