Jim, I think I have a little bit of born in Missouri, the show me state, in my blood. I have always heard that the canister stove fuel would not evaporate enough below freezing or there abouts to run the stove and if it did run, you would burn off the part of the blend that evaporates first then you are only left with the part that needs higher temps to evaporate. I wanted to try my Pocket Rocket on this trip to see what I could get it to do and save a little weight. Now I know what is required, plus, I don't have to sleep with the canister in my sleeping bag to get it to start in the morning. I had planned on staying out for seven nights, but the fishing was poor and I didn't like the wind above tree line, so I was only out for five nights. I was southwest of Mt. Whitney. A small canister will last me a week in the summer, so I brought a large cansiter, thinking the water would be colder and take longer to heat up, plus give me some lee way.