I have to upgrade from my old Sigma 70-210 APO 2.8. I will be shooting for professional print in the near future and the Sigma is not sharp enough. I've seen photos from a newer 70-200 and they look great. My question is, which one should I get? The Sigma is a DG lens, meaning it won't work on full frame cameras - if and when I get one. The Canon L lens is obviously more expensive, heavier, but has incredibly image quality and is built like a tank. I am an intern photojournalist for a local newspaper and will be shooting action sports portraits - lots of different sports too. Of course, either lens is good for the future - for a while at least.