Lanyard is plenty long and it makes lots of sparks (after a couple of scrapes to remove the paint). If lanyard was not long enough one could exercise ingenuity and put on a longer cord.
It would easily light propane, but if you try to ignite a piece of sheet paper you will have trouble. Sheet paper is not fine enough and is not proper tinder (though you could shred and rumple it to make good tinder). You need a finer tinder bundle. Paper towel was also unsuccessful. I had easy success with toilet paper and dryer lint. It sparks more if you slow down and increase pressure a little. If the woods are wet and you can find no dry tinder you are in trouble, which is why most people carry tinder or fire starter or pick it up on the trail when they can.
I think it is easier to use the magnesium fire starter with a basic metal jigsaw blade as the magnesium shavings will ignite paper towel easily, and can also ignite paper if you make a dime sized pile of shavings (when igniting paper don't set the end of the magnesium fire starter on the paper as when you scrape the flint the vibrations will jiggle the shavings all around). Even better than a jigsaw blade may be a short hacksaw blade because it has a good hole you can put the cord through.
In summary: if you carry or can find/make good tinder the Swedish firesteel is tough, simple, and a good product. For normal people who want a firestarter that is somewhat easier to use carry the magnesium. That is what I will carry, in addition to good tinder (cotton balls with vaseline mushed in), and a very good lighter (more lights/space than matches).
P.S. Just watched Bear G. in Man vs. Wild (Discovery channel) use this after a major rainstorm starting a fire on the first strike BECAUSE he had previously harvested and protected some very good tinder. He did not use a magnesium firestarter. It does produce a 5,500°F spark, but it needs a purchase (tinder). Also I want to repeat that the lanyard I got was plenty long, but hey it's just a piece of cord that you can cut. Live bold. Also the first time I tried to make sparks I made plenty. I do not see how someone could not (unless they had the metal striker upside down - read the directions!).
P.P.S. Watched Bear G. in Ecuador (?) NOT be able to start a fire with grass using this because everything was wet and darkness came in not enabling him to search for better (dry) tinder. With typical Bear pluck he stuffed his shirt with the grass for insulation and kept his chin up. I bet the mag would have started a fire.
P.P.P.S. Watched 'Survivorman' take a mag starter out into the desert and easily start a fire, but he used the edge of his knife to make shavings and strike the flint. I don't reccomend dulling a knife like this, use the back or anything else. Also he CARVED off magnesium and I have found just SCRAPING works well. Finally on the magnesium starter the flint is a small rod on the side and you don't whack it like in Jeremiah Johnson, but you just scrape it. I think I read one reviewer that broke his flint and I bet he was whacking it, just like in the movies.
This is a long review because this is a survival tool and you should have confidence in it's capabilities.