Comet Cleaners on Kelly Avenue in Edmond recently changed their sign to emphasize the same benefit that Parkway Cleaners in Edmond began touting a few years ago: they are environmentally friendly because they don't use toxic solutions to process the clothes. In particular, they both switched from the perchloroethylene method of dry cleaning to the more eco-friendly, less-toxic pressurized liquid carbon dioxide (CO2) system. Larger urban market dry cleaners that made the same switch tout themselves as being organic however I believe there are no real differences between Parkway, in example, and a typical "organic" dry cleaner. In Oklahoma, "organic" is perceived as a premium (ergo, more expensive benefit) that may not be worth the price difference. Parkway emphasized "eco-friendly" during their switchover. For my money, the greatest attribute is the neutrality of odor - things smell clean, not dry cleaned.