Most Underrated K mount lens

In the interest of balance I thought it would be fun to look at peoples opinions of the other side.

I would like to nominate 2 lens

1 the Pentax f/fa 501.7 , Over shadowed by the imo inferior 50/1.4's to the point production was ceased this lens is sharper and has a more pleasing bokeh.

and

2 the DA*300 a truly wonderful prime ignored in favour of the 60-250 zoom and the DA*200 f2.8 both of which it out performs by some margin (especially @300mm )

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