So, while on the COZS winter camping trip, we discovered we had all three of the LMF firesteels handy, and decided to pit them off head to head.
First, a picture of the relative sizes. Top to bottom we have the mini, the scout model and the full sized army model.
Madwolf was first messing with the mini he had with him, and could not for the life of him get the tiniest puff of flame, after trying for a ridiculous amount of time. This is the size apparently lots of folks get because it's small enough for a keychain, yet hey, it's a firesteel, right? Well.. apparently so, but first problem was a lacksadasial spark, and then th ferro rod popped out. It also did this on Squirrley's, so we were 2 for 2 on the ferro rod popping out thing. It does go back in, but yu'd think they'd use a bit of glue on it when they put it together. All in all, we graded the mini firesteel a fail. You get spark, but even someone with quite strong fire-fu could not get a flame in the mountains in winter with it. But I'd deem it perfectly safe to carry in your pocket. If we couldn't light a fire while trying to, I doubt your pants are in much danger unless you carry powdered magnesium lint around.
apparently I forgot to turn macro focus on for the close ups. I claim brain freeze.
For slightly more weight you get the scout model.We then managed by pretty much pure luck to get a nice sparky picture.
As you can see, not bad sparks, and it lit the tinder pretty readily. All in all, we rated the scout model as definately useful, and maybe portable enough for keychain use. note: ferro rod has not popped out of mine (the one used for testing) thus far. Probably safe for pocket carry, but you might want to consider just putting it in a coat pocket instead of your pants. Just in case.
Last we have the Army model. This is the one that was actually tested directly after the min. I think madwolf was on his third or fourth strike when he almost lit his pants on fire when the tender he was testing suddenly flared up. Here's the luck imbued sparky picture for comparison with the scout:
As you can see, much larger sparks but a slightly larger ferro rod. Ok, so this one's freaking massive, but if you're camping and want a fire, this is the one you want to have handy. We rated it as a "Crap, I ought to pick one of those up!" Probably don't want to walk around with this in your pocket, you'll either stab yourself in the junk constantly or it'll touch your keys for a millisecond before you're caught on film and misidentified as spontaneous human combustion.