If anyone is looking into getting an air filter I recommend winix it was tested by project farm and scored the highest. also I am the owner of two and they've been working great for 4 years now I run them using auto and never worry about them again, the automatic sleep mode is bliss.

replacements are cheap on aliexpress coming at around $30 (per year). You don't need true hepa replacements, you can skip carbon filters if you don't have odor problems or have lots of ventilation.

the filters are pitch black every time I replace them so they're definitely doing something.

I do however recommend skipping all of that and just getting a box fan with a lower-tier merv filter since at the end of the day airflow matters the most and it turns itself back on if the power goes out plus it gives you the ability to tie it into home automation.