Surprised to find 4 pages on manual pumps. It seemed like all the cool kids used CO2 for a good bit but are now migrating to those little electric pumps.
My brother in law gave me a CO2 kit. I haven't used it. I don't trust it. I'll empty the cartridge prematurely or something. And CO2 leaks after a day. What if I need two or three cartridges? My pump is more reliable.
I learned a good tip for using CO2 though. If the cartridge isn't enough to fill your tire and you want to use it with a pump, better to do the pumping first and letting the cartridge top you up. If you use the cartridge first, topping up with the pump takes more force since the pressure is higher.