Are you shooting medium/large format or 35mm? If 35mm and you "hate grain" then I would most definitely go with Delta 100. As many have said, they are more similar than different. I shoot MF and much prefer FP4 which I still find extremely fine grain. I develop in FP4 in rodinal frequently to bring out its grain and amazing sharpness. But if I were shooting 35mm I may not do so.