What a refreshing drink!
We used raspberries frozen from last year. Forgot that when berries are frozen they tend to compress a bit so probably ended up using more berries/juice than recipe called for. But, what a lovely color. Not quite Husker Red, but close.
We figure this recipe might be a good option if some of your picking assistants with those little hands tended to smush a few berries. This works well whether berries are smushed or not.