For the price the air purifier is relatively quiet on the lowest setting. Unfortunately it is not quiet enough for me to keep on when it's bed time. The timer function is a nice addition. The unit came with the two filters already installed but it looks like swapping in a replacement will be very easy. The initial day or two there was some odor as the filters were 'initialized'. I have noticed this with either vendors and types of air filters so far you leave it running in an open space for a day or two it will be fine. The air vents out the top so it is a good design for floor or shelf placement. I'm not sure I would buy his product again.