The Tokina 16-28 is a great piece of kit and is often my go to lens when I am after a sharp crisp image. The 2.8 is great for astro and lowlight photography.
I have owned the lens for over a year now and it is built like a tank. I’ve used the lens in all sorts of conditions and weathers and it has always performed well. The lens is a lot heavier than some of the Canon alternatives which I use.
Baring the recent release of the Canon 16-35 the Tokina is the sharpest wide angle I have used. There is softness and vignetting towards the outer edges but this can easily be corrected in Lightroom.
The only downside to this lens (and the reason it doesn’t stay permanently attached to my camera) is the fact it cannot accept filters.
Well worth purchasing if you have the spare money 🙂