Dropped to -1c when I was at Kielder, I couldn't get my Trangia lit. The person in the next tent lent me there gas stove.
The procedure for lighting a Trangia in extreme low temperatures probably doesn't work with the Mini or Triangle, as it depends on being able to suspend the burner above the cap (with o-ring removed, and a small amount of fuel burning within, possibly using something as a wick to get it started).
I've lit a Trangia burner straight from the freezer by spilling some meths on the top of the burner and holding a cigarette lighter to it, but that took some effort, and was in warm air. The coldest I've used it in the wild has been a little above zero.
It's the opposite problem to gas at low temperatures: Once you get a meths burner going, it'll keep going. With gas it'll light instantly, but the butane won't boil quickly enough to keep up with demand. The proper solution is a stove with a pre-heat loop that can run on liquid butane from an inverted cartridge (the Trangia gas burner is such a design). The bodge is to immerse the cartridge in a pan of liquid water, increasing the supply of heat to the boiling gas.
Camping at well below -6°C in the Netherlands in January I had problems with both the gas cart I had taken with me for my multi fuel stove, and my meths stove. The gas cart/multi fuel stove combo gave a puff of flame, then wouldn't respond. No fuel flow, nothing. I was suffering from frost nip already, and couldn't face trying to persuade the gas to work, so switched to the meths stove. At this temp, I was 15°C below the working temp for meths to burn properly. I tried the plenty of meths and a lighter approach, but that didn't work, I tried flint and steel, ferro rod, I even used a lump of flaming cotton dropped into the meths. In the end the solution that worked was a NATO wind proof match dropped vertically into the meths so it could prewarm a small area, and wick a little. Eventually the stove lit. I was using a Evernew Meths burner.
The evernew burner has a higher heat output, but also uses about 50% more fuel than the trangia.
AIUI the drinks can burners make up for their incredibly light weight with increased fuel consumption, but YMMV.
Yeah, a lot of stoves are very fuel inefficient. I have a Zelph starlite stove, which is very similar to the speedster stoves. It's the most fuel efficient meths stove I've found (I've tried nearly a dozen), it's very light, and you can pre fuel it if all you're expecting is a single burn. This pre fuel ability also means you can stick it, fuelled, in your sleeping bag, or coat pocket, or cleavage to warm up.
If you want reliable, light, and compact, then the MSR Micro rocket is a very good choice. Needs a wind shield like any gas stove, but you can often get away with a rock, or a bag, or even your own body.
J