Summary: I would buy this again, despite the lack of scroll function. You get used to using the bar on the side of the window, and I think the efficiency of the trackball makes up for this inefficiency in other areas for my personal use.
Pros: Good little trackball. Works well and is efficient for large screens or limited space. Inexpensive. Easy to install. Seemingly well built.
Cons: As others have mentioned, the ball sometimes sticks but it is a minor issue. The ball can fall out if the device is tilted. My biggest issue is that there is no scroll. That would have been a deal breaker but I thought that was a basic feature of any pointer device. Like a camera in a cellphone. ...
Pros: Trackball movement is very smooth (clean off any dust from the ball before you first use it); scroll wheel feels really natural; detachable rubber-like wrist rest is comfortable.
Cons: Buttons feel "chunky" in that I have to apply a little more pressure than other mice. I prefer buttons that respond to a lighter touch. Their "click" seems almost loud in comparison to other devices.
Summary: If you like making use of more then two buttons on a mouse you will be out of luck.
Pros: I have put 3 years of heavy use on this mouse and it is still functioning smoothly. Scroll wheel is a little odd to get use to but definitely comes in handy.I'm able to scroll with my ring finger while my thumb and pinky remain on the buttons AND my middle and index are able to remain on the ball...
Cons: None. price was very fair for what I got out of it
Excerpt: Lower cost alternative to more expensive trackball offered by Kensington or Logitech. Inclusion of scroll ring was major reason I purchased (aside from price). Some people may find ergonomic not to their liking but for myself it was a perfect fit.
Pros: Accurate Controls, Ergonomic Layout, Fast Response, Smooth Movement
Excerpt: mice are a pain, even the ones which have multiple buttons and so forth, because you always run out of space with them, or end up with your arm stretched across the desk, and about to knock off the coffee cup, too. Enter the trackball with scroll ring. XLNT!
Pros: Accurate Controls, Easy To Clean, Ergonomic Layout, Fast Response, Saves Desk Space, Smooth Movement
Excerpt: In standard trackballs (e.g. Logitech), the ball is further away from the palm of the hand (compared to the buttons) than in this one. In the beginning, I thought, I can't work with this but after a week or so, it worked fine. The scroll ring is an excellent idea of course.
Pros: Accurate Controls, Fast Response, Smooth Movement