Does anyone own this lens made by Sigma? I'm curious as to pros/vs cons. selling price is only $210. Any advice would be great! Here is the information on the lens provided from the sigma website "these lenses incorporate a macro feature with maximum magnification 1:2 at the 300mm focal length. It is suitable for various types of shooting conditions. The 70-300mm F4-5.6 DG MACRO for Nikon is a telephoto zoom lens with excellent value for money and optimized for use with digital SLR cameras. This telephoto lens has a 1:2 maximum magnification at the 300mm focal length. It is ideal for portraits, sport and other types of photography. SLD (Special Low Dispersion) glass provides excellent correction of chromatic aberration. The super multi-layer coating reduces flare and ghosting. High image quality is assured throughout the entire zoom range."