I've been pottering around the last few days trying to 'winterise' my trangia. What I've come up with is an old baked bean can (actually I think a tinned pea can), both ends cut out, and sliced down the side to open it up a bit and allow enough air in. It acts as both a windshield and potholder for a SP 900 saucepan with the burner sitting inside. Then I drilled some holes in the can about 1.5" up and zigzagged some wire through to hold the trangia above the ground (stops the ground conducting heat away = faster heating), and to allow a little tea light candle to sit below it to heat it more in very cold conditions. One trick I've also heard when it's very cold is to take the o-ring out of the trangia lid, pour a small amount of meths in, light it and sit that under the burner instead... apparently gets it going in no time which I quite believe.
I posted a while back that I'd had a small problem with meths leaking from the edges of the burner. Well I finally got round to emailing Trangia about it and less than a day later I had a reply asking for my address so they could send me another one. That was a couple days ago so assuming it turns up I'll be very impressed with their service.
In the meantime I'd bought a cheap highlander (I think) burner off ebay and I've continued using both the civvy and the swedish army one. A few nights ago I did a semi-scientific test of them all to see how they performed. I filled them up with about 2/3 fuel (recommended), weighed them, lit them, timed how long it took for them to start burning at full power, weighed them again at that point, timed while all the fuel burnt, then weighed them once again. Through that I could calculate fuel burn / time - it's power - and by far and away the winner was the civvy trangia. It was fast to heat up so the jets were working, and you could tell it was better than the others by the stronger and more bluish flame. The Swedish one seems bombproof, but it's heavy and takes a long time to heat, while the Highlander one doesn't (I would guess) have enough jets.
This might all sound quite obsessive, but I do like the trangia and I would like to take it with me on a few week long trips this winter. Even with pans, windscreen, pot cosy etc it's still lighter than my nova (my usual winter stove), and although the nova's a great stove you can't really beat the trangia for reliability.
The others I've been looking at recently are A. the jetboil, which I think is an excellent stove in all respects apart from that it's slightly too heavy and gas by it's very nature isn't so good in winter, and B. the Svea 123R for it's simplistic reliability.
Trouble is I think it's a bit too easy to start becoming a stove-a-holic!