Excerpt: I have always preferred the trackball. This Logitech is a well made and reliable unit. The wireless works well. Battery life seems strong as I have not needed to replace the included battery and the life estimate in the software shows it will last many months yet. It was easy to install and set up. Ergonomically, it is smaller than older models that I have owned and this is moderately uncomfortable as I have very large hands being 6'4" tall.
Pros: Accurate Tracking, Fast Response, Glides Smoothly, Great Features
Summary: great replacement mouse for my Microsoft Optical Trackball mouse which Microsoft discontinued. This was the only other model mouse with the trackball on the side that I could find. And a great price too.
Excerpt: It works great. Have to get used to the trackball being on the side & not in the middle as our old one was. Like the scroll roll that allows you to do it automatically or by clicking on the menu. It will be just as useful as our old one, once we get used to it. I would recommend it to anyone who likes this type of mouse.