Blueair Blue Pure 511i Max vs Winix 5520

Small-room specialist against big-room contender, and on paper the Winix 5520 is the stronger air purifier overall, backed by a higher AHAM Verifide smoke CADR than the Blueair Blue Pure 511i Max, a longer 2 year warranty against 1 year, and a deeper filtration stack that layers a certified True HEPA filter and a switchable PlasmaWave ionizer onto its washable pre-filter and carbon layer. The Blue Pure 511i Max has the edge on two fronts that matter for a bedroom purifier: it is the more affordable of the two, and it is the only one here reading PM1, PM2.5 and PM10 separately rather than a single PM2.5 number. Coverage tells the rest of the story, the Winix 5520 is rated for 392 sq ft at 253 CFM, well beyond the Blue Pure 511i Max's 237 sq ft at 153 CFM, and it draws far more power doing it, 50 W against 17 W. Both work with Amazon Alexa, stop short of Apple HomeKit, SmartThings and Matter, and rely on Wi-Fi for their smart layer. Choose the Winix 5520 for a bigger room and certified filtration, or the Blueair Blue Pure 511i Max for a quiet bedroom unit with sharper particle sensing and lower running cost.