Originally posted by Jodokast96 I was thinking that myself, but then couldn't recall anyone here even using a Tokina lens.
I have a Tokina 400mm F5.6 "A" lens and a Pentax SMC A F5.6 lens and end up using the Tokina more mainly because it is shorter and lighter and I can hand hold it while I use the pentax with a tripod.
I think the reason we don't see more Tokina AF stuff for Pentax is the fact that Hoya owns both companies and perceive Tokina Pentax mounts as competing with Pentax.
I think Tokina has always used Hoya glass also.
As far as ranking, it is hard to do because as pointed out, everyone has there stars.
Pentax's SMC A zoom lenses never lived up to the SMC A prime couterparts and Tokina was always a better option. The trouble with some of sigma's vintage lens was the cement they used would let go or turn yellow with age but my only direct experience with that was with the Sigmas that my grandfather used on his Minoltas.