Alen BreatheSmart Flex Alen BreatheSmart Fit50 vs The Alen BreatheSmart Flex and BreatheSmart Fit50 are both very popular HEPA air filters that are packed with nice features. The Fit50 model comes with more features and a higher price tag, but the Flex is certainly not lacking in functionality if you can’t afford the Fit50…. [Read More]