1) What do you plan to use the mouse for?
2) How much are you willing to spend?
Do you prefer a claw or palm grip? Do you want a mouse which can be physically adjusted, configured, customized? Right-handed or left-handed or ambi? More buttons, less buttons, programmable profiles and macros, particular LEDs and colours and styling, etc? Do you need high dpi, fast polling, quick response, special calibration, prediction features, etc?
"All opinions are not equal. Some are a very great deal more robust, sophisticated and well supported in logic and argument than others." - Douglas Adams
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