I use the Sigma 2.8 24-70 as my walkaround lens on the D7000 and am quiet happy. When travelling OS it stays on the camera and works very well.
Regards John Nikon D750, Sigma 105mm OS Macro, Tokina 16-28 F2.8, Sigma 24-105 Art, Sigma 150-600C, Benro Tripod and Monopod with Arca plates
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