DIY Electric Ignitors are awesome, we covered that in the making DIY Electric Ignitors post, but to ensure they work you need to test them.
You need to be certain they work well before you attach them, because a hooked up ignitor that does not ignite on command is dangerous.
If it has a delayed activation that occurs while you are around the pyrotechnics then you can die. Its not the dying that is bad, its the fact that it will HURT the entire time you are dying.
TEST a few of the ignitors in every batch before you use them.
Especially if the ignitors are improvised.
As you can see this batch had a bit of a delay. That was because I used copper wire as an electrical bridge rather than the more effective nichrome wire.
This means it took longer for the wire to heat and ignite the compound.
Knowing that the ignitor has a delay is important, but because of it, I would not use this in any large display. This would work better for lighting a fire like I mentioned in the original post.
There are many ways to make these ignitors, and any search of a rockety club will show you how.