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@moth
Lots of strokes = an inevitable consequence of small pumps.
I have the slightly longer 120mm one as an emergency, carry everywhere pump. With some fat rubber bands cut from old inner tubes i bind it and a small adjustable spanner to my puncture repair kit to make a pack i can thread my belt through. I've used it in anger about half a dozen times and got on fine with it.
I've got the schrader head with presta adapter which seems to be the most common. The adapter slows things down a little, but it all works and seals well. You can keep the adaptor screwed into the nozzle, but it's easier to fit it to the tyre before the pump so i keep mine in my repair kit. Adaptors are a generic component, so cheaply and easily replaced if you loose them.
Pumping force is set by the internal cross-sectional area of the cylinder, and the airbone's 254mm^2 is slightly larger than the two other mini-pumps i have to hand for comparison (210mm^2 and 190mm^2 for the forward strokes of a wrench force road and an old blackburn). That works out to around 175N for 100 psi, (~the weight of an 18Kg mass) - that's only the last part of the last few (tens of) strokes. Getting up to pressure i can rattle it back and forth pretty quickly, and generally find it comfortable enough to pump.
The other thing which limits pumps is how much air they compress but fail to push past the non-return valve so that it just re-expands as the piston is withdrawn. In the airbone's favour, it has it's non-return valve built into the head of the plunger, about as close to the working volume as possible, but it lets itself down a little with a pump stroke that stops 2mm short of the cylinder end, and even with a full stroke the protrusion on the plunger would reach only a third of the way into the recess in the end cap. Not wonderful, but i've seen far, far worse. (You've just prompted me to try improving mine - i'll let you know how it goes.)