Instruct: Classify Amazon reviews into positive or negative sentiment
Query: The only choice!

My Microsoft Trackball Optical is pretty much worn out, and I needed a thumb action device again. I tried the Apple mouse with my new Mac and started having arm trouble again. I found that it this point the Trackman Wheel is actually the only thumbball you can still buy. I also remeber now why I did not buy one years ago when I bought the Microsoft one, the Logitech is smaller physically. My hand has since made the adjustment, but I wish there was a thumbball that was larger than this one.