When we landscaped about 5 years ago, we needed an effective screen to hide the neighbor's property. I selected Photinia x fraseri. Great stuff as it grows quickly and provides nice color year round. However, despite my best efforts, I was unable to keep the Photinia from falling victim to leaf spot. Fungicides kept it at bay for 2 years, but this year is a disaster. I give up and need to find a suitable replacement. What might you suggest?

It needs to be evergreen and tolerate full sun. As I need 6-8 feet for adequate shielding, something that grows quickly is desireable. Cost could also be an issue as the hedge is 165 feet long. Mission impossible??? Suggestions welcome. Thanks! Dennis