The Tokina AF-X Pro 16-50mm f/2.8 DX is a decent lens with efficient autofocus, excellent image quality and very solid barrel. Common complaints with the lens include high vignetting, huge chromatic aberrations at lower focal lengths and weak performance at larger relative aperture.
Nevertheless, it can still be appealing for users seeking lenses with smaller minimum focus distance, more manageable filters and more compact size. The out of focus blurring (bokeh) performance is particularly buttery smooth at 50mm and f/2.8. Barrel distortion can be mitigated by choosing longer focal lengths. Users will also appreciate the accurate and responsive AF performance.