Winix 5500-2

Mid-range air purifier rated for rooms up to about 360 sq ft, using a washable pre-filter, a true HEPA filter, an activated-carbon layer for odours, plus a PlasmaWave ionising stage and an air-quality sensor with auto mode. Weakness: the carbon and HEPA filters add ongoing replacement cost and the PlasmaWave stage can be switched off if ionisation is unwanted.