This air purifier is wonderful.  Even though it is larger in size than I expected, I found the controls to be very user friendly.  I was able to easily start and understand the different modes without consulting the instructions.  The unit runs quietly and works perfectly.  I closed the door on the room it was in and noticed the difference immediately when I went back in a few minutes later.  While appearing to be high tech, it is unassuming and with the ability to select night mode and time-out functions, it works well in my spare bedroom. Nice product!