Another gear update regarding stuff moving toward the outside of my circle of trust -
My BRS 3000-T stove gave me 2 years of light use, then 6 months of meh performance. Eventually it stopped producing a flame, even indoors with sufficiently full fuel cans. Given that I feel I've solved my winter alcohol stove issues (going to a FF stove, wick-style, instead of putting the pot directly on a side-burning cat can), I'm leaning toward going to just alcohol stoves.
I replaced the BRS with a Coleman Peak 1, with the intent of using up the rest of my canister fuel, then mothballing the Peak 1 for any future time when I might want a stove during an open-flame ban, such as is common out west and which sometimes occurs during southeastern drought conditions.
This weekend I took one of my remaining canisters, a Coleman "Performance Blended Fuel" 220g canister that was 2/3rds full. This is a propane / butane mix, and I would not be surprised if the propane burned off already and it's mostly butane at this point (assuming the fuels can separate in the canister - IDK). It's my understanding that butane vaporizes at 31F. This weekend my first AM temp was 50F and the second AM was 60F.
No trouble the first night or AM. Stove worked fine. Second AM, when it was actually warmer, it conked out doing the same type of 1-2 cup water boiling. I found the can had (as expected) cooled a fair bit, but it didn't feel like it cooled THAT much. Nevertheless, I put the canister between my thighs for 5-10 minutes and tried it again - and it worked. Though for good measure I kept my hands on the canister while it was in use. When I came home the can was 41% full by weight.
I may just use up that canister at home. I have another canister, a 110g Snow Peak that is about 80% full. Probably a better mix, but I don't know how much more I should trust canisters just because of that. I see that Hikin' Jim has raised a caution about these Coleman canisters (orange label), but more in the context of working/not working, rather than temp-based failure. So in my case, it was probably a fuel-mix issue rather than an incompatibility issue with the stove, but I am still surprised that it got too cold to use at 60F ambient temps. That orange coleman canister definitely won't go into the woods with me again.