Although I've never used a CO2 inflating system...I'd think that the cartridges are pretty standard. Maybe I'm wrong. But I'd think the head is where you'd want the best/reliable device. As much as I'd like to elimate frame-mounted pumps from my bikes...I'm too pessimistic about CO2 inflation systems. Too many times I've seen riders go to inflate and the CO2 cartridge just go PFSSSSSSSSSST into the air and the tube/tire not get inflated. Since most of my riding is alone I have to maintain a pump, and don't see the sense of carrying both systems with me.
Dan