I've fired mine, I have one burner for three machines, and did have a rather "blazing" experience the first time. So I modified the burner in a manner that can be undone, thus originality is preserved. All I did was make a "tube" of fine brass mesh screen to cover the wick opening on the poker, but also packed the poker with a very tight wick to help slow down the wicking action a bit.
Oh yeah, and I also used some K&S brass tubing to be able to make the flame slot in the poker smaller.
The real key, as with most alcohol burners, is to not overfill it!!!