Attention science folks! Anybody attempted to use Nitrous Oxide (N2O) cartridges instead of Carbon Dioxide (CO2) in their pumps? It's a lot cheaper to buy a box of 'em at the local Smart and Final (or head shop for some of you!) and at the end of your ride you can suck the gas out of your tubes for a nice cool down! Would it be safe? Would it last in the tube?