The weight was also a key factor in changing my mind. I had expected the lighter prop to spin up better, and then I had a plane that needed the CG just a hair further back. I could add like 1/2 ounce of lead to the tail, or go to a wooden prop. It didn't take long for me to decide to try the PZ then. In the end, the CG shift amounted to almost nothing, but the props performance opened my eyes a bit.