This man speaks the truth. In my experience, the activated charcoal filters are worth the added expense.I only buy the activated charcoal filters. They make for a more pleasant cabin. The activated carbon removes most, but not all, of the bad smells before they enter the cabin. They also stop small amounts of aromatic hydrocarbons (i.e. that overly rich running carburated Camaro spewing fumes in front of you at a light!) from reaching the cabin. The standard filters filter pollen and some dust only.