Wouldn't it be funny if Plus-X were actually just a reformulated/sensitized Panatomic-X such that the speed gain is there? Maybe Pan-X is just a less sensitive long scale film as opposed to something like Pan-F which is a true slow speed fine grain film. I'd think Plus-X with an ND filter or just shot at a slower speed could offer a pretty decent low speed medium contrast replacement. Certainly not worth pining over something that disappeared ages ago and we know will never come back in it's original form.