Like the Explorer Touch Mouse, the M600 is glossy from head to toe. That's a great idea... if you like smudges. At 11 cm long, it isn't optimally sized for the human hand—your palm doesn't rest on it. Another drawback is the weight distribution. Once the two AA batteries are inserted it becomes back-heavy, with the back end of the mouse swerving annoyingly every time you make a brusque movement.
The minimalist shape makes the M600 usable for both lefties and righties. Unfortunately there's no thumb button, no matter which hand you're using.
Contrary to appearances, it does have a scroll wheel—a virtual scroll wheel. With your finger you can scroll vertically in steps or continuously to get quickly to the bottom of the page. Sliding your finger horizontally has an entirely different effect. When you go from right to left, that takes you "Back" when you're online or navigating through folders in Windows. And going from left to right takes you "Forward" in your web browser or Windows folders. Basically, Logitech has replaced the functions normally performed using your thumb with the horizontal touch axis.
With everything except for the left-click, which acts the same as on any mouse, the M600 takes a little getting used to. This is in part due to the clicking system. Basically, there's one physical button covering the entire mouse and it's where you touch the mouse on that button that determines which click you're performing. For a left-click you press down with your finger on the left-hand side of the mouse. If you keep that finger held down and then press on the right-hand side of the mouse with a different finger, that also performs a left-click. If you press on the mouse without hitting the touch zone, that once again does a left-click. When you press down on the right-hand side only, that does a right-click.
The wireless signal is sent from the mouse to your PC via the USB receiver. It's a small one—it sticks out only half a centimetre from your port; that way you don't risk ripping out every time you walk past your computer. On the other hand, it's also easy to lose if ever you remove it.
The M600 is perfectly suited for web browsing and your typical office-type usage that doesn't require precision by the millimetre. However, a more demanding public such as, say, graphic designers, may not find it useful with its 125 Hz frequency.
A gaming mouse requires a sensor capable of detecting
speeds of over 3 metres per second.
Same goes for the speed: the M600 maxes out at 1.2 m/s. That's too slow for gamers, especially FPS players (games like Call of Duty, Half Life, etc.) who need to be able to turn around in an instant. For other types of games, however, this won't necessarily be an issue.