I have only been using my 45i for 2 weeks! This unit is extremely quite and is appealing to the eye! I use this in my bedroom, I suffer from allergies and asthma, and I believe I am less congested since using my 45i My furniture is dark and I have noticed a little dust, but not as bad as before. I think I will try the "pure" filter next time. I would advise anyone to try it!