The T-grain films (Ilford Delta 400 and Kodak TMax 400) have a real advantage for grain size. TMax may have slightly smaller grain, but many prefer the look of Delta. Kodak 400TX has very fine grain, but much larger than TMax. The thing about 400TX is that the grain is soft looking and not obvious in viewing the whole picture. The old Agfa 400 speed product had very noticeable grain, but a nice look to the pictures. For most shots, grain doesn't count as much as people think. The great shots taken 50 years ago were all made on film with much coarser grain than any modern film has. With ordinary films, you can soften and mask the grain to some extent by using a fine grain developer like Microdol, D-76 (undiluted) or D-23 (undiluted).