Need to get a new wide angle zoom & am deciding between these. I can get a great deal on the sigma, but not sure if it's worth it, or if I should rather spend more & go for one of the others:
Tamron SP AF17-50mm F/2.8 XR Di II LD Aspherical [IF]
Tokina AT-X 165 PRO DX AF 16 - 50mm f2.8
Sigma 17-70mm F2.8-4.5 DC MACRO
FOR USE ON NIKON
Any other suggestions welcome too!!!