No kidding! Have you seen the "rough example" of the (computer) interface to be able to micro-adjust focus for a zoom at different focal lengths
and different focal distances!?
Just crazy good stuff. Sadly, I fully expect Sigma's "new" 120-300mm/2.8 with this function (also weather-sealed, with HSM & OS) will be just like the previous models and never be made with a K-mount on the back...
We're just a small (and shrinking) marketshare, and I'm sure Sigma sees "no compelling business case" for Pentax users to buy a full-frame lens like that one. (And before you jump in - yes,
I see the reasons to buy a lens like this for APS-C!)