SHORT REVIEW: Do not purchase unless you already have seriously strong fingers; will provide a strenuous challenge for individual fingers. Should provide a moderate challenge for those just interested in working on full-hand grips. Five stars for utility and quality.LONG REVIEW: If you're like I was, you probably think the Gripmaster series is for strengthening your grip. This is one of the uses of the Gripmaster, but the intended use is improving individual finger/thumb strength. Sure, the individual tension pads should be a dead giveaway, but Gripmaster ships with limited instructions on how to use it. Prohands clearly hopes that you will take an extra five minutes to visit prohands.net to see their 11 exercises.I would recommend visiting the site: many of the exercises are not intuitive and will come as a pleasant surprise. My favorite exercises work the daylights out of the thumb, a great help for a console gamer such as myself.With that said, this model has 11 pounds per pad. I thought I had a strong grip (I've used traditional "nutcracker" grip strengtheners for years), but when this model broke down my grip into individual fingers, a little humbling was in order.If you have a weak grip and want to improve individual fingers, I would advise starting with light or medium tension, and work your way up the tension scale. This model is not the place to start.Two final notes: Pro Gripmaster models are bulkier than the "regular" variety and have rubbery covers on the pads. I don't believe there's a difference in pad tension (i.e., Extra-Heavy is going to be 11 pounds per pad on both models), so if you have smaller hands - or just want to save a few bucks - the regular Gripmaster line should do the trick.Finally, both Pro and regular models are extremely well-made devices and appear to be relatively indesctructible.