At what speed should a Morse code "CQ" call be transmitted?

A fundamental rule of Morse code (CW) etiquette is that an answering station will reply to a CQ call at the same speed the CQ was sent. Therefore, you should only send a CQ at a speed you are comfortable receiving. If you transmit faster than you can accurately copy, the answering station will likely reply at that high speed, and you will struggle or fail to understand their transmission. While you might be physically able to manipulate a keyer at a very high speed, your transmission speed must always be dictated by your cognitive ability to decode the incoming reply.