Have you compared Copex Rapid and Spur to Ilford PanF+? You mention that you've used it but in your comparison above you only compared it to FP4+, which I must say enlarges impressively to 16x20" from 6x7 with no grain I can see in the prints. PanF+ 135 enlarges effortlessly to 11x14" with great sharpness and no grain I can see so obviously I'll have to try it out to 16x20".