I have had my purifier for just over a year now, and I love it. The LED mode light can be turned on/off if you don't like the disco feeling. It is also quite shocking just how much dirt there is in the air. I change the water every couple of days and it's grey. We also use the purifier a lot when either myself or my partner have a cold to save the other one catching it and it does help.
I am now in the process of getting one for a friend who is very keen on it. It does work and now they've come down in price it's worth getting a couple - one for the bedroom and one for the lounge.