I never used a noise machine for my DD. Actually... I used to purposely alternate the level of noise in the house. Some nights, I would keep quiet. Some nights, I would just carry on the normal level of noise. Sometimes I would run the vacuum or wash pots and pans when she was in bed.
Now, she has a fan in her room... Not for the noise, but for the cool air. lol. She is able to sleep through anything... Heck, we had a NASTY thunderstorm a few nights ago... with thunderclaps that woke me from a dead sleep hard enough that I jumped out of bed, and she slept right through it.
It's sad though... I have had to turn on a fan in my room for temperature control, and now I NEED it for the noise. I am typically a super light sleeper, and it has helped me a lot to sleep through things that used to wake me up.