Just received a Tamron SP 70-200mm f/2.8 VC Di USD lens. I have to say this lens is every bit as solid as the Nikon equivalent. Sharper too by just a hair. Here is a wide open shot of my little buddy. ISO 6400, D800e, 195mm, 1/50s handheld. Processed in LR5.2 + DxO Filmpack 4.