I've heard nothing but praise for Mikes work.
But if you fancy a go yourself, get an old metal file and snap it to length in a vice covered with a cloth ( to stop it shooting off into a dark corner and to save your eyes) then carefully and slowly, grind off the teeth from the edges and a little way around the faces of the file. What you are left with should strike good sparks and last for ages.
ATB
Ogri the trog