 They're big. They take up a lot of space. Every month you've got to change the filters, which costs you a lot of money. It's going to have a long cord that you might trip over or the pets might knock over. It's just a pain. And you're not really sure it's going to get what you want it to do. The Eden Pure Thunderstorm will go and seek out and destroy mold, odors, viruses that are in the air using O3 molecules. It's Oxy technology. They send out those O3 molecules throughout the house to seek out and destroy those odors. And again, it's even where you can't get to.