I have, and I hate them. They're fairly heavier than the Penn balls I usually play with, and it kinda hurt my wrist hitting a flying rock...
Also, they have crazy topspin when you first start playing, and they move viciously fast. I ALWAYS wait for the ball to bounce then fall before hitting, but with the ProPenn I was hitting on the rise pretty much every time. Once they hit the ground, they soar up to the sky and way past the baseline.
The friend I played with is about equal to my playing level, and I could handle him when focused. But today I was losing like there's no tomorrow. I simply couldn't handle the pace and bounce.