In all seriousness, they are good, regular maintenance of the filters pays dividends and the ability to have them running constantly certainly works well in this place. The Silent "Sleep Mode" is a boon too.
Usually, in Spring, Summer and Early Autumn we have most windows and exterior doors open, but in winter, being an aged Sold Brick construction, we guard our costly heating. It takes a lot to get the solid walls warm, so apart from at night, the heating ticks over constantly.
IF I were to reinvest, I'd go for a larger Purifier in the lounge, but you lives and you learns