Whichever, from the experience of a number of Heathrow controllers in the past, neither worked as intended, for crews still managed to make distracting transmissions, such as "Hello tower, XXXXX, we're with you, monitoring one one eight five, where would you like us..." etc. A number of us adopted the unofficial "Listen", for it seemed to get the point of it across, and was certainly much more effective that 'standby' or 'monitor'. It certainly made for a quieter life with fewer distractions whilst one organised the optimum and most expeditious departure order. It is unfortunate that "Listen" was never adopted. It is certainly one-word, one-meaning, understandable, unambiguous and, above all, effective.