First, I have to give a HUGE thanks to Bzzagent! for sending me this awesome portable air purifier!!! 
As soon as soon I flip it on I can feel the air becoming fresher and "lighter". It's not meant to purify the air of large spaces, however.. it is perfect for a bedroom or an office! It has two modes, low and high. The air is made much more fresh with the high setting but the fan on this setting is a bit loud. The fan is a slight hum on low, that is barely noticeable.
The filter is very easy to switch out with a latch located on the bottom. It came fully charged to purify for hours right out of the box!!
It truly does freshen up the air in small areas really well! It will definitely be put to good use! Especially in my office!