I'm not big fan of CO2 either unless I was in a race than I would use them otherwise no way. Why pay for air when you can get it for free? Why have a waste product when your done using it? Problem with those CO2's is that most riders when they have a flat throw the damn spent cart onto the side of the road where they fixed their flat! I see that schit all over bike paths and lanes including their stupid energy wrappers. Take your trash with you and stop being pigs out there those of you that do that nasty schit, and you know who you are.