I am a recent convert to CO2 usage on the road. I have observed that my CO2 inflated tires do not hold pressure as long as pumped tires. I thought it was just me, that I'd done something wrong, but I guess others have observed the same thing.
I resisted using a CO2 inflator and always carried a Road Morph pump with me (which is a very nice pump, imo). Unfortunately, the RM does not fit on my new Ruby and I was forced to carry a mini-pump. It works but it's a MUCH greater pain the in rear. So, I pulled the CO2 inflator out of moth balls and now carry it and a few cartridges on my bike as well as the mini pump for back-up. It's a compromise: neither one by themselves is an ideal solution.
Another thing: those little empty CO2 canisters are recycleable. Any empties I might have after a ride are put right into our recycle bin for weekly pick up and we've had no complaints so far.
Jane
Every human being must be viewed according to what it is good for; for none
of us, no not one, is perfect; and were we to love none who had
imperfections, this world would be a desert for our love.
--- Thomas Jefferson