I had heard about heavier weighted balls before and never tried them. I have to admit these are awesome. 5 minutes of 3 ball Cascade was an incredible workout. If you've only juggled with basic balls then this will be a challenge. Had to start all the way back from the basics to retrain my mind how to throw these properly. They do not roll away. And it might sting a little bit if you drop it on your foot but you're not going to break anything unless you throw it like a baseball at someone. I am really happy I bought these.