Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Disappointing - Poor design

As mentioned previously, great trackball, poor design.I took a chance anyway and I now still have to try and find a proper trackball mouse since this one has a dreadful fault making it unusable.The design makes your wrist bend backward too much as the ball is too high, guaranteeing RSI in no time. The supplied wristrest is useless (too short for big hands) and feels cheap (not silicone).A shame as the trackball itself has a nice size and feel to it.The ball should be inclined forward, not backward. If that means a smallerball, then so be it. Users serious about their trackballs should look elsewhere.Note to Kensington : the wrist should never bend and the hand should always be in the alignment of the forearm ! Hint : look at the first Microsoft trackball design...What a waste.