Lens Comparison: Nikon 55-200mm vs Sigma 70-300mm

[cheguthamrin]

I read about this;

Nikon 55-200 mm F/4-5.6G ED AF-S DX Nikkor Lens

Nikon 55-200mm F4-5.6G Lens is a versatile and ultra-compact zoom lens with a powerful focal length of 55 - 200mm. Nikon 55-200mm F4-5.6G Lens is designed exclusively for Nikon DX format SLR's (Single Lens Reflex). It is an ideal 3.6 x zoom lens for portraite photography, sports event and wildlife photography. Nikon 55-200mm ED DX Black Lens is an excellent companion to the "AF-S DX Zoom-Nikkor 18-55mm f/3.5-5.6G ED Lens". It is equipped with new compact rod-type Silent Wave Motor (SWM), which enables ultra-high speed autofocus with outstanding accuracy and super-quiet focus operation. Nikon 55-200mm F4-5.6G Zoom-Nikkor Lens is finished with Super Integrated Coating (SIC), which minimises the ghosting effect and flare, a known problem of Digital SLR cameras. Nikon 55-200mm offers outstanding optical presentation and provides even higher contrast and more vivid images in challenging light conditions. The lens groups is equipped with two ED [Extra Low Dispersion] glass elements in order to achieve reduced chromatic aberration and superior optical performance. Nikon 55-200mm has Focus Mode switch, enables quick-switching between AF (Auto focus) and MF (Manual Focus). Nikon 55-200mm F4-5.6G Lens has 9 number of rounded diaphragm blades for more natural out-of-focus highlights. Nikon AF Nikkor G-Type lenses features more compact lens designs and include D-Type technology that_provides_the camera with distance information_for flash and ambient_light_exposure_processes.

So should I get that?
...but I already have this.
Sigma 70-300mm f4:5,6 APO DG Macro Telephoto Zoom Lens

Sigma 70-300 mm APO DG Lens is one of the best lenses ever produced for Digital SLR Cameras by sigma. Sigma 70-300mm Apochromatic (APO lens) is corrected for chromatic aberrations in all three primary colours. Sigma 70-300mm offers tele-macro function and is furnished for digital SLR cameras. The telephoto zoom lens is capable of shooting with a maximum magnification of 1:2 at the focal length of 300mm. Sigma 70-300mm DG Lens is the highly recommended lens for portrait photography, sports, shooting nature, and other types of photography that most often use the telephoto range. It has two Special Low Dispersion (SLD) glass elements one each in the front and rear lens group. It embeds APO technology for excellent correction of chromatic aberration through the entire zoom range. The new Sigma 70-300mm Lens is capable of macro photography with 1:2 maximum magnification at a focal length of 300mm. It is designed with new multi layer coating reduces flare and ghost, which is a general problem with digital cameras. Sigma 70-300 mm Lens also creates an optimum colour balance through shooting with maximum magnification 1:2. Sigma 70-300 mm f/4-5.6 APO DG Macro lens demonstrates high optical performance throughout the entire zoom range. Sigma 70-300 mm f/4-5.6 APO DG has a purpose-built switch that adapt the lens to macro photography at focal lengths between 200mm and 300mm with a minimum focusing distance of 95cm (37.4 inches). In normal mode the minimum focusing distance of It is (150 cm) 59.1 in at all zoom settings. Maximum magnification of the lens between 200mm and 300mm is 1:2.9 to 1:2.
Sigma 70-300mm Lens has added characteristics as compare to many other lenses. Salient features of Sigma 70-300mm Lens are its Apochromatic function for colour correction and aberration, telephoto lens with longer focal length and narrower field of view than a normal lens and enlarges distant subjects, and last but not least with zoom capability allow a continuously variable focal length.

Read over and over, but noly making me blurrr...