We affectionately call our BreatheSmart 75i "Alen." Alen always knows what's going on - whether you're cooking, vaping, or just hanging out, we joke "Alen knows what you're up to!" or "Alen knows what you've done!" I love that he can detect the janky air from far away in the house, and that he always works hard to make clean air for us. My husband has allergies and I have a mold sensitivity, so I feel safer in my home knowing Alen will change colors if the air quality changes.