Instruct: Classify the given Amazon review into its appropriate rating category
Query: Had to return it

The included "unifying" receiver does not work with my Logitech keyboard. Fortunately the 5 year old keyboard receiver magically works with the new mouse, so at least I didn't have to waste a USB slot on another dongle... but what's the point of buying Logitech if the "unifying" receiver isn't backwards compatible? Update: The left-click was failing to register often, which was becoming very annoying. Had to send it back.