We replaced all of our iQair purifiers with Alen BreatheSmart. Alen units are far more economical, quieter and have improved air quality (we have instruments to measure it) by 50% over the iQair units. Look carefully at the power requirements of competing units, especially iQair and you will find the power consumption of the Alen BreatheSmart is much lower. When it comes time to replace filters, iQair filters cost as much or more than many of the Alen purifiers and they do not last longer than the Alen filters. It is an easy win, especially with the lifetime warranty from Alen.