Ok, throw another camera in the mix. I picked up a 28mm f2.8 Yashica ML lens for my Yashica FX-3. Realizing I use the Nikkor zoom on 28 almost alll the time.
8 more rolls processed yesterday and again, the Nikkor is pretty fantastic in comparison, with excellent edge sharpness at 28mm. The Yashica has an edge in sharpness in the central area, but there is the typical pattern of oblong blur in the tree leaves in the upper corners.