Any question answered...

^yup

^^16g gets you up to about 120, 12g a little less. I carry 12g cartridges. They'll get you home but CO2 seems to escape the tyres fast, so you'll have to pump up properly next time you take the thing out. You get a little bit of flow moderation with that mini head, but it's pretty much a binary thing.
That fucking explains a lot!!!