More time with the sticks, The Pro-one reminds me of a lighter more comfortable PS-97. It's doesn't go through the ball as easily and feels softer overall, not as dangerous but it's also .5 ounces lighter with a swing weight of 310 instead of the 320 of the Pro-Staff. It tends to hit a little flatter than the Pro-staff as well. I spent some more time with the Formula Penta core. It's 11.4 ounces strung with a 310 SW as well but feels more head light than the Pro-0ne in my hands. This guy has serious pop. It's actually pretty controllable except on volleys. It does not have the deft touch of the pro-staff or the Pro-one. Volleys kind of go...BOING!! Serves were a blast with this guy. I have no idea what string they use or what tension.