Hey guys I was looking at a cheaper telephoto lens and these are the two I've been looking at. The Sigma 70-300mm f/4-5.6 SLD DG and the Nikon 70-300mm f/4-5.6G AF non-VR. I was hoping you could give me some input and point me in the right direction on which lens to get. I currently own a d5200 and a d7000. Thanks in advance.