I don’t understand, the cheaper IKEA purifier (FÖRNUFTIG) uses its entire front side, covered with fabric, as the pre-filter. To clean it, you stop the purifier and vacuum clean the front side, which takes 15 seconds.

The more expensive round one (STARKVIND) doesn’t use its fabric covered front as the pre-filter (it’s actually solid) and instead has a separate fine mesh (not that fine though) layer underneath. To clean that, you have to take the front side off first, which takes a bit longer.