I tested both the G903 and the G703 with a variety of games to see how well they performed, and how efficiently they charged. Both methods let you play while you charge. By contrast, charging Logitech mice with a USB wire takes about 2 hours. A representative from Logitech estimated that it would take 14 hours to completely charge a dormant mouse on the PowerPlay mat, and perhaps five times that long if the mouse is in constant use.
If you're planning on taking your mouse elsewhere, you should be aware that the PowerPlay isn't the fastest way to charge it by a wide margin. You can monitor a mouse's charging status with the Logitech Gaming Software, although you won't really have to.
If your wireless mouse has ever run out of power in the middle of a game, the PowerPlay ensures that you'll never have to deal with that inconvenience again.
