Logitech Ergo M575 New Version Wireless Trackball Mouse, Easy Thumb Control, Precision and Smooth Tracking, Ergonomic Comfort Design, Windows/Mac, Bluetooth, USB - Graphite Extra Battery Bundle

I can't talk about the usage and performance of all of you people that want to play with "Microsoft Windows". I'll stop there. To each, his own. For a "Unix", "BSD", "Linux" user, this may be the best trackball out there. With the opensource solaar, you can incorporate this and any other "logitech" device into operation on your PC. The Logitech M575 mouse gives unparalled precision.

I love this thing. Works great for CAD

My wife has worn several of these out over the last 29 years. This (unlike some of their gear) has remained a solid and durable unit. One caveat: you have to pop the ball out, remove any grunge from the three contact points in the socket, clean the ball and reinsert it about once a month or so (more often if it sticks). The product is designed to be cleaned.

I just wrote a nasty review that hopefully will get scrubbed. I was upset about the USB dongle missing but after some searching learned that it is in the battery compartment. Apparently you just have to know that because I didn't see it in the instructions. I'm a big fan of Logitech products have been using these trackballs for years. Much better than a standard mouse once you get used to it. I'll continue to recommend them to friends.

After several years my old M570 finally kicked the bucket so I decided to go for the new model.....positives the dual wireless dongle/ bluetooth combination is handy the slightly bigger size I like as well! But The left button randomly sticks since day one, the ball is not as smooth as the M570 and not a huge deal but it was advertised as a "Extra Battery Bundle" which simply was not true....makes me wonder if it is truly the newer version of the M575.