I have a Trangia that I like. I bought one for myself (just the burner) and one for my daughter (the entire Trangia cook kit with windscreen, etc.) and she reports it heats slowly. I understand that alcohol burners are not going to be fast, especially if she's comparing it to her pressurized gas outfit. She is thinking that her burner might be defective.

So I just did a side-by-side test of the two burners. Inside. 65 degrees. No wind. Both performed identically. They each bloomed after about 30 seconds or so. Then they both had fairly tall flames (several inches) for the remainder of the burn, mostly orange for the great majority of their flame height. Some blue color right where the gases escape from the holes in the burner. I am using Yellow HEET for fuel.

Is this typical for a Trangia burner? I always assumed so (I've had mine and used it longer than my daughter has used hers). I don't have any other Trangia burners to compare these two against. They certainly don't settle down to a nice controlled blue-only flame like you can get with a pressurized gas stove. But I didn't really expect that. I think my daughter did.

haertig... I use Klean Strip S-L-X denatured alcohol in mine, and get mostly a blue flame with a little yellow/orange...burner only

FYI, Klean Strip Green is only a buck more and has less junk in it. I think it has a higher ethanol content.

Sounds normal to me. I have three Trangias scattered about and they all perform in a similar fashion to what you describe. They are slow compared to a canister stove, but they get the job done. Most especially they are rugged and fool proof. There isn't much about a Trangia to become "defective."

Mine behaves differently depends on what fuel is in it, methanol will give steady low blue flame while ethanol gives yellow high jumpy flame.

Interestingly my soda can penny stoves behaves the same way.

i would suggest you try a few different types of fuel and see what the results are.ask around to some camping/survival/hiking type friends and see what they have so you don't have to buy a gallon just to see how a quarter cup burns.
make a afternoon project out of it,try a few pots and see how they work and so on.
i have the Trangia cook kit with the windscreen and pots that are made to fit and use all the heat and this kit works very well as a water boiler while a Gaz stove does the real cooking.
i used Sunshine brand alcohol in mine and can get a rolling boil in minutes to heat a can of stew.the only drawback with these type of burners is that when they run dry it can be tricky to remove the pot of half cooked food and the hot burner to refill it.
the burners are not very expensive so some campers have a second filled and ready to go,the hot one allowed to cool down a bit and refilled to be swapped if need be to finish the meal.meals which are simple and filling seem to work best for this type of stove.
get a real Trangia,i have a knock off and while it does work it's not as solid and the seal on the lid is not %100.
the big ones in the Army cook kits are whoppers and really run hot and long for a alcohol burner.

Also be aware that pot diameter, distance to flame etc. will have an effect on performance, slow can be much slower.
The brasslite web site explains it very well.
I have both there stoves and trangia but the info. is useful for either
style.
Caldera Cones are something else to look at.
I use a home made Alu. flashing wind screen with my stove and
surround the pot with about a .5in pot to screen gap, it really helps.
Don't forget to punch some vent holes near the bottom of the screen or your stove can overheat. I only surround mine about 80% and punch vents as well.