I have had pretty good luck with them so far. knock on wood...

I usually buy whatever is on sale and rotate my stock every couple of years. The last batch I bought were the Calico brand made in Thailand. I have had them for a couple of years now and each one has performed reliably. In addition to using it to seal the ends of cut 550 cord, I will spark them to test them once in a while just to make sure they still work.

The most recent "test" was when I inadvertantly left one in my pants pocket and it went throught the washer and dryer before I noticed a couple of days later. I dug it out and it works fine. Only the sticker label got a little mushed up, but who cares. It is translucent so I can see the fuel level is still good. Has lit every time so far. I have tried it a few times over the past two days. I was expecting the flint to disintegrate, but nope, still ticking.