I am looking to purchase a fairly good 70-200 2.8f lens for my Nikon D300. I am an amateur photo. and need a lens I can get good indoor shots at a sporting event. I was eyeing the Nikon 70-200 2.8f VR ($1,900). I spoke to a camera shop and they recommended a Tamron 70-200 2.8f (no VR) at 1/3 the price. Am I going to be loosing a lot of quality and functionality going with the Tamron? Is the Nikon lens 3x's the quality and build? I checked some Internet reviews on the Tamron. The most common complaint for the Tamron was the slow focus speed and lack of focus (some times). The Tamron sharpness and quality was said to equal the Nikon. I have not seen any bad reviews for the Nikon lens. Anyone with some experience using these two would be much appreciated. Thanks!