We have used it since around 5 mths too for colds and they are wonderful! Also one thing we have found is that the ducted heating dries the air terribly. We discovered that a few of our vents have a sort of shape in the bottom so we can pour about 2 cups of water in each one that can take it! This helps keeps the air moist while the ducted heating is on - you can also place a bowl of water over the top of the vent if you don't want to tip it in like we do! HtH!