Hey everyone, have been using the Blueair Pure 211 air purifier for over 4 years now. In the polluted environs of Delhi-NCR when we all start choking around mid October, we start thinking of ways to get cleaner air, especially if we have small kids! Im happy to say ive had an excellent experience with this Blueair product. Its perfect for a large sized bedroom and in terms of technical stats like CAGR its counted among the best. Another good thing is there is no ionizer, so no ozone byproduct formation which is known to aggravate allergies. One downside is that there is no inbuilt air quality monitor, but when you know its bad - just let it run! There are 3 fan speeds - its extremely aesthetic, at the low fan speed its extremely quiet. The HEPA filter ensures a very efficient cleaning process and more importantly the pre-filter cloth that comes in attractive colours helps to increase its life. On the whole, it’s reliable, sturdy, efficient with excellent build quality. I changed the HEPA filter after 2 years of use and its scary to see how black these filters get. All that was otherwise going into your lungs! They advise to change the filter every 9-12 months!