Sorry, didn't see this until now. It casts very well on the Project One 8wt. I doubt anyone will say the Project One is light in the tip, and this line doesn't help that, but it slings it well. I made some 70' casts with a fairly heavy Hybrid and a 13' leader. It wanted even more.
It shoots well, as expected with the big head, but I was impressed with the amount of line I could also false cast without shooting.
It's probably a great popper line. I haven't had a chance to cast my biggest poppers with it yet, but it's definitely in the plan.