I bought one of these (Xiaomi Pro H) over 3 years ago, to have in my office space at work. It's never…

I bought one of these (Xiaomi Pro H) over 3 years ago, to have in my office space at work. It's never registered the need for a filter replacement. Checking, it's still at nearly 50%, after 3 years. My wife uses one in a classroom, a larger space, and has similar performance. https://t.co/uyibwiZTjb

As context, I use mine only in a smaller space (cubicle), and don't run it at full speed (I use low, or medium at most). I'm told running these units for prolonged times at high speed can cause them to fail, but for my space low to medium is fine.