FWIW, I've shot a few rolls of Neopan SS (35 mm) recenty, processed in HC-110 1+79, 13 minutes with agitation every 3rd minute. I wasn't terribly impressed with it; the grain was comparable to what I get with Tri-X in the same format, using film that expired 5 years ago and spent part of a summer in my van. Fomapan 100, aka Arista .EDU Ultra 100, is much finer, and sharper, in you choice of HC-110, Rodinal, or Diafine.
OTOH, since you're going to be shooting 18 or so rolls of the Neopan SS, I'd suggest sticking with high solvency developers like D-76/ID-11 stock solution, HC-110 Dilution B, etc.; these will tend to soften the grain and make the film look less gritty. Whatever you do, do *not* develop Neopan SS in Rodinal; even if you like grain, the grain from this combination is just ugly...