When I bought the F version of this lens about 15 years ago, people kept telling me the FA version had better optics. But at that time it was more expensive and I couldn't afford to buy it then. I found this one on the Marketplace here for $30, and bought it. Seller never mentioned how bad if focused. And unfortunately for me, I didn't ask.
If there is ever a next time on buying older lenses here, I'll ask to see photos taken with it recently.
Thanks for allowing me to switch. I now have the Sigma DL Macro-Super 70-300mm f4 - 5.6 on the K-30 blue boy.