As butane is transferred from the container to the butane torch lighter, the pressure will cool down the butane. Before you can use the lighter, however, you will need to let the butane rest for some time. The resting period will heat up the butane to room temperature, which is important since butane will considerable expand as it reaches room ...
Butane does leave a residual film when it burns and not all of the butane sold on the market is completely free of contaminants. What that means is that your torch lighter or dual torch will need to be cleaned and bled if you want the flame to be optimal for cigar lighting.