Here are my options. Sigma 120-400mm f/4.5-5.6 DG APO OS for $650 or Canon 70-200 f4 IS L for $950. I know how great the 70-200 is for portraits, and thats one of the reasons I want this style lens, but I also want good zoom capabilities. What do yall think? I would love some input, I am going back and forth in my head, need some experienced photographers input.