There is very little difference between HP5+ and Delta 400. In terms of sharpness and grain, it's very difficult to see any significant difference. Subjectively, I do find Delta prints appear crisper at normal viewing distances, but closeup inspection with a loupe does not support any significant advantage in terms of sharpness or resolution. I prefer the tonality of Delta 400 over HP5+. It exhibits a slight rise at the shoulder which affords excellent highlight separation and an almost 3-dimensional look. For this reason, too, I like skin tones on Delta 400. Delta 400 may also have a slight advantage in terms of real speed, but both films offer excellent latitude and shadow separation.(posted 8160 days ago)The bottom line is, I think HP5+ is a great film and it was my first choice (and still is in 4x5) until Delta 400 was improved. I use Delta 400 now, but if it were discontinued, I'd survive quite happily by returning to HP5+.