The Sigma 70mm - 200mm is an awesome standard zoom lens for Canon cameras and a really good alternative to Canon branded 70mm - 200mm lenses. Want to see just how good the Sigma 70 - 200 is? Check out this article for an honest and unbiased review. This article also lists the 5 best Sigma lenses for Canon cameras as of today.
Sigma 150-600mm F5-6.3 DG OS HSM | Contemporary - A hyper telephoto lens featuring the same focal length and brightness as our Sports line lens yet developed to fulfill the Contemporary line. Which one is for you? The Sigma Global Vision website can help you answer that question. http://www.sigma-global.com/en/lenses/cas/product/contemporary/c_150_600_5_63/