The differance is in the tips and probably the regulators. If you backfire a regular O/A tip you can clean them with a tip cleaner and a file...... Propane ,if I recall the tips are vained if it pops back its time to buy another one. I have two sets Oxweld and Smith. I have used accetagin(spelling??) with oxygen and it just is not the same. If you realy want to save money set it up with natural gas. that will work also, like propane. When I worked a Reynolds they even had a burning table that used water( cut 6" steel). Anything will work, to me its just how hard do you want to work