What to buy? Sigma 50-150 f/2.8 or Tokina 50-135 f/2.8?

I have not yet decided what to buy. Although these lenses are discontinued, they are still available in my country. I know a little bit about these lenses so I need to have an expert's opinion, like their pros and cons. I have the Nikon D5000. I want to keep a good lens for myself in the long run.

The tokina will not autofocus on your camera, not sure about the sigma but it does not autofocus either I thinbk.

I like the tokina, build quality and handling is superb! Optically there's not much difference, high end zooms the bo th of them