This is some of the lenses I am looking at. Which of these do you think is best for my Nikon D7100. I do horse photography specifically alot of jumper events. I want clarity and a good amount of zoom. If you think another used lens within the 500-650 bracket is better than I am open .
http://www.ebay.com/itm/Tamron-70-200mm-F-2-8-Di-SP-LD-IF-Lens-for-Nikon-Digital-SLR-Cameras-/172362628019?hash=item28219cfbb3:g:q84AAOSw8w1X8mmc
http://www.ebay.com/itm/Sigma-EX-70-200mm-f-2-8-APO-DG-HSM-Lens-for-Nikon-/332181310563?hash=item4d578c8c63:gxcAAOSwB-1Y7kVB
http://www.ebay.com/itm/Tamron-SP-A009-70-200mm-f-2-8-VC-Di-AF-USD-Lens-Canon-/152506977664?hash=item23821fcd80:g:ZsYAAOSw4CFY7RS3
http://www.ebay.com/itm/Sigma-DG-70-200mm-f-2-8-APO-HSM-DG-EX-OS-Lens-Nikon-/142350003109?hash=item2124b8aba5:g:OC4AAOSwc-tY8iaW
http://www.ebay.com/itm/Tamron-70-200mm-F-2-8-Di-SP-LD-IF-Lens-for-Nikon-Digital-SLR-Cameras-/172362628019?hash=item28219cfbb3:g:q84AAOSw8w1X8mmc
http://www.ebay.com/itm/Sigma-EX-70-200mm-f-2-8-APO-DG-HSM-Lens-for-Nikon-/332181310563?hash=item4d578c8c63:gxcAAOSwB-1Y7kVB
http://www.ebay.com/itm/Tamron-SP-A009-70-200mm-f-2-8-VC-Di-AF-USD-Lens-Canon-/152506977664?hash=item23821fcd80:g:ZsYAAOSw4CFY7RS3
http://www.ebay.com/itm/Sigma-DG-70-200mm-f-2-8-APO-HSM-DG-EX-OS-Lens-Nikon-/142350003109?hash=item2124b8aba5:g:OC4AAOSwc-tY8iaW