Not half-bad...
This unit makes a pleasant background noise, similar to the "whoosh" of a well-made fan.  It has two speeds, high and low.  I find that the high speed produces a tone that I find distracting, so I use it on the low speed.  It isn't loud enough to fill the entire room, so you might consider purchasing two of these if you are serious about screening out sounds from the outside world.  You'll want to place each one between where you work/sleep/read/whatever and the door or window that is letting noise into your room.  It does seem to work better if you elevate it off of the floor by placing it on a table, stand, or chair.  I find that it compliments my portable fan nicely.  With the two of them placed strategically in my living room, I can work or read without being disturbed by common street noises or the conversations of my neighbors.
Rating: 4 stars