I added 2.5lb at flame out to a Newcastle clone hoping to give it a slight peach flavor. I was disappointed. I feel like it only made the beer sweeter and did not add much flavor or aroma. Maybe adding more might help?
A brewery here is Spartanburg, SC makes a Peach Wheat called Son of a Peach, which is what gave me the inspiration. I do know they use fresh local peaches but not how much or when they are added. But their beer have a strong peach flavor.