I have used 120 HP5+ for years, and when the Delta films came out, I decided to give them a try. I would agree that the Delta films showed a slight increase in sharpness. But that was about it. They seem to have a thinner base and are more subject to curling. The price difference is also a factor to consider. I shoot a a lot of 120. I decided to stick with the HP5+. I develop it in PMK and have always had excellent results.(posted 8052 days ago)Don