Currently the need/desire for a new telephoto lens has given rise to a search for advice. I now find myself shooting my daughters’ outdoor sports events as well as wildlife in the Wasatch Mountains of Utah. I am somewhat obsessive compulsive about detail. Currently I own a 70-200 and a TC-20E II and would like more reach, detail and cropability (academic license). My inventory also finds a disappointing, to me, seldom used 80-400. The new lens will be mated to a Nikon D2x and a Gitzo 3530 tripod with RRS BH-55 head. The Nikon 400mm and 200-400mm are looking like good contenders. I would also be willing to buy a TC-17E II to enhance range when needed. Any thoughts, contrasting viewpoints, and experience good or bad would be greatly appreciated.