The best Fire Steals (Ferro Rods) are the Light my Fire military versions.
I have used several, Primus, the magnesium blocks, the very thin ones, wrapped partially in steal (that you'd get in survival tins) and other generic ones.
The Light My Fire ones (get the military, not the Scout) are the best. The striker is very good, sharp flat edge (saves your knife) and the rod is very thick, and has they approximate to be 12,000 strikes.
I have two. They are a little pricey (circa 14.99-15.99) but I love them, they are tried and true, and I will be buying two more (each one will be permanently stored and dedicated to each of my stoves).
As far as stoves go I love the Primus Omnifuel, but that is a different conversation, but have many stoves, and admire a wide range of manufacturers.
I mention the stove, to demonstrate that I am not just going with a big name (e.g. Primus) for the sake of it. I have tried many and found the Light my Fire to be the best.
Also, the two I have are slightly different. I have a 'mark one' and mark two. The mark one has a larger metal striker, whereas the mark two has a smaller piece of metal, but a thumb piece made of plastic. I was sceptical at first, but now love it. TBH I am not sure which I would choose, but the performance is the same.
You will find different strikers are all very different. The ones provided with the magnesium block style have a saw blade, which eats away very quickly at the ferro rod, and therefore I would avoid this. The magnesium block is a great idea if you are concerned you may be without tinder, but try another striker, even the back edge (still needs to be pretty sharp) of your knife. The Primus ones have three issues. 1.) The rod is thinner than the Light My fire, so has a shorter lifespan. 2. The striker is wavy - not quite serrated, but again fairly aggressive, which leads to faster wear on the rod, and less accurate striking when aiming the sparks. 3. The elastic lanyard is two short, and you have to stretch it every strike which is both frustrating, but also restricts the accuracy of the sparks.
Long story short, Light My Fire
http://www.amazon.co.uk/Light-my-Fire-s ... +firesteel
There should be both old and new models on there. If you are going to be in very cold weather perhaps get the newer versvion, but otherwise, go with the cheapest.
Serious, I know its only a fire steal, but I just love this one!
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