I'm rather surprised by a lot of the comments on here. Trangias are very easy to light! The windshield helps, after all. You light a match, hold it to the alcohol... and it lights. It can take several attempts, particularly if it is raining, but it's rarely more than that. If you literally can't light it you're doing something quite wrong. I personally use a firesteel to light mine, that I keep in the yellow burner bag. That way I know I never need to worry about it.
Additionally, Trangias work in almost every single condition found on this planet. They love the wind, where they'll burn high and hot. They shrug off blizzards, and pouring rain. Even if they didn't, they can (unlike gas cookers) be safely taken inside the tent as they never flare. I have personally used them in temperatures below -40 degrees celsius. The only difference in operation is that a different fuel is used (as methylated spirits waxes, I imagine similar to the way that petrol does, at about -30), which Leon tells me is naptha. That, and if you touch the metal stove you'll be very very stuck to it, although of course you'll have little or no bare skin at that temperature. They are more than game enough for snow melting, which takes an incredible amount of time for any stove (can be two whole hours or even more for a big pan). Unlike gas, no preheating or anything needs to occur, nor do they lose pressure. This summer my Trangia broke my fall from about twenty feet, onto solid, hard, ice - with the result that there's a tiny dent in the lid that I'll be able to show my grandchildren - because I can confidently say that it'll still be working then
Adi, I think the problems with people on Ten Tors were not that the stove let them down, but that people didn't know the kit they were using. The only time I have given up trying to light the stove was in a total whiteout, and for the reasons that if I'd sat still much longer I'd not have got up again (never mind my hypothermia, I'm talking about snow drifting onto me and clothes freezing solid), and that snow was filling the burner faster than I could even pour fuel in, never mind scoop out by hand. And I'm sure that but rarely happens on Dartmoor, respectful as I am of conditions there (done TT twice now, was hoping to run the 55 with my running club but sadly it will have to wait, not to mention many weekend walks) - and I'm nothing special! I'm sure there are people who would make my Trangia-using abilities look like a zebra trying to do needle work.
Edit: that came out as a bit of a rant, sorry folks!
PS I accidentally used petrol in my 27 series once... apart from the 9 foot flame it was brilliant, if a little sooty. Has not harmed it the tiniest bit, amazingly. Although it did manage to set light to my mate's hair, and scarily singe his passport and bus ticket... but that's a story for another time