This is a great gadget. Didn't seem like my thing but I brought one for my boyfriend for christmas and he loves it. It also causes arguments because as it turns out I love it too. The counter on it is the best thing as you can keep track of your progress so I wouldn't recommend buying the cheaper one without the screen.
The ball can sometimes get sweaty and start to slip out your hand if you go too fast and I also have a blister on my pinky (probably from probably using it a bit too much!) but I can't help it, it really is that addictive. Another problem is that the clear score button is the same button as the on button but this doesn't cause too much trouble if you know what your doing. The gyro can be a bit loud so you might find yourself watching the television with the subtitles on while playing.
Even after the competitive arguements and blisters it is really worth getting your hands on one of these as it has helped my arm muscles already and has brought a whole new level of being competitive into the house.
Really worth the money and blisters! 5/5