Consumer reports rates this very highly. I wonder if they tested it in a real installation. Most homes with a vented exhaust have a 4" round duct (same size as dryer vent). This one requires a 6" round because the blower is too weak to handle the additional back pressure of a 4". Unless you want to do major renovations in your kitchen to install a 6" round duct, avoid this one. It's extremely loud and the blower speed fluctuates wildly (no doubt due to our 4" exhaust duct). The requirement of a 6" duct is ridiculous.