Sheila, at some point, more oxygen cools the flame. I'm sure that's why it's hotter, but not a huge difference. Your smaller concentrator almost has enough to get to the top of the hill, but not quite... and if definitely can't give you the cool oxydized flame. This is useful when working a lot of boro colors. You need oxydized ,but cooler, to keep it from boiling. That's really the bennefit of having more oxy flow in the way I work.
If your torch doesn't require the higher pressure, it's not worth getting an M-20. The M-10 has about the same volume... spend the money you will save on glass if you can.
Feel free to call me any time.
