You use more oxygen with propane than with acetylene. But the difference in price more than balances out to propane having the advantage cost wise.
With a regular acetylene torch with a propane tip, you get a slightly colder flame. This was over come with the torch that was designed specifically for propane, it is carburated differently. I believe an outfit in Red Deer was building them, have some info on it somewhere as was considering getting one a few years back.
I have always used propane myself and have also used acetylene many times over the years when working out, and with your flame and pressures set right, I find little difference. Possibly a bit longer preheat with propane on heavier materials.
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