I love using the powerball, it is really addictive and I end up spending a good half an hour on each arm a night. I spend most of my time on the 30sec runs, which is suposed to improve strength. My fastest run with my left is about 9700, as opposed to the 11,225 on the right. Have you seen the
www.powerballs.com website? They have a leaderboard for a number of different catagories most of which are topped by some greek guy, with videos of him going mental with it.