Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Nice concept - poor quality

I bought this for my laptop because the touchpad can sometimes be problematic. I really like the concept, but the construction quality is poor. The main problem is the roller pins that contact the track ball. If you are not holding the unit in a specific tilted position, the pins won't make proper contact and you can spin the track ball forever and the mouse pointer will go nowhere. I would gladly pay more if the constuction quality wasn't so bad. As it is this item is not worth more than a few dollars. This is essentially a dollar store item.