When I saw how quick and easy it was inflating Mark W's flat tyre I was impressed and so was Mark. Both of us bought a 'Genuine Innovations' mini pump and Mark ordered come bottles of CO2 in bulk.
He offered to initially spilt his haul 2x ways, then 3 ways and then 4 x ways. This little lot of 13 CO2 bottles cost the bargain price of £6.50. I must say that I suspect this represents an almost lifetime personal supply as I have only ever suffered one puncture so far.
Of course the point of having these on a trip is that if others in your group had a flat they would be more than welcome to use up one of these bottles if it meant they got going quicker.
Now that I know how to change wheels on my Brompton if I or one of my fellow riders suffers a puncture, I am confident that things will be sorted out pretty quickly.