Like a lot of people who live in flats we have elephants for upstairs neighbours. The elephants above us don't sleep, ever, so they are stomping around at every hour of the day and night. Up to now my wife and I have been using ear plugs to sleep, which are uncomfortable and not always that effective.
This is the first and only white noise machine we have had. It does take some getting used to; at first we put in ear plugs as well as having it on, and it took a little while to get used to having this noise constantly in the room. However after just a few nights we didn't need the ear plugs, hardly notice the noise, can quite easily get off to sleep and aren't disturbed in the middle of the night by noisy neighbours! In all honesty we're pretty light sleepers as well, so this is a great result.