Good Morning, Michael,

I think you're right about not being able to detect any appreciable difference, even with somewhat bigger enlargements. As for the "one stop wider" idea: With 4 x 5 B & W negatives, exposure times, even using 11 or 16, are typically not very long anyway, at least up to 16 x 20 size; using a larger lens opening could even be a disadvantage if any dodging is involved.

If money were no object, I'd probably replace all my enlarging lenses with APO versions, but I doubt that my prints would look much, if any, better.