Obviously you're getting a lot of opinions by people who haven't done critical testing. All the later Schneider,
Rodenstock, and Nikkor lenses will work well, but the premium Apo-Rodagon lenses will provide better fine gradation and a bit of extra sharpness. It's hardly worth it unless you're camera lenses and film are also equal to
the task, because 20X24 is quite a bit of enlargment for such a small negative. But if sheer crispness is what you're after, spending more and getting the apo lens will help. The only truly better enlarging lenses out there
are the Apo El Nikkors, which are dramatically more expensive, and I'm unaware of anything shorter than 105mm
in that series. I personally use a 150 Apo Rodagon for medium format, and it's conspicuously better than the
Compnon S lenses for both black and white and color use. It's also faster for all practical purposes (better corrected at max aperture or just one stop down).