I truly love(d) the Microsoft Explorer Trackball and the Logitech Trackball Wheel, having each attached to a computer in my house. When I attempted to find either for my third computer I discovered they're extremely hard to find unless you're okay with really expensive, formerly used trackballs. I saw that this New Sanwa Trackball Mouse looked very much like the Logitech Trackball Wheel at a reasonable price so I took a chance. It was well worth it. It feels just like the Logitech, maybe a bit smoother. It is slightly larger, but that's okay. I would recommend it.
BUT worth it ! Comfortable, stylish, and not much room required. It is absolutely perfect for me, and it looks like it will last a while. Wireless just don't work for a mouse, too many batteries, but basically too much trouble.
Hard to find the product anymore. Wired thumb controlled trackballs are hard to find and most have gone to wireless. Wireless is not a good option for businesses, so I'm always looking for good wired thumb driven trackballs of good quality.
After using this trackball I am very impressed with the performance. The ball moves smoother then Logitec and overall performs better than Logitec trackball.