All depends where the added weight is. Put it all at 12 and a hollow racquet is still going to feel hollow. I did that with my stripped down Juice Pros. From what I've seen, the actual specs of the Speeds are all over the place. Neither of the PPs that I've hit with feel underpowered nor have a SW below 329. What I like about it is how you can accelerate the racquet head pretty easily and then use the mass in the hoop to go through the ball, yet it doesn't feel HH. If that's modern weight distribution, I quite like it.