I got a firesteel based on all the talk about them on this damn forum. I got the Firesteel 2.0 scout and have only used it to make sparks. It's pretty cool.
I also have and have used the Mg block with a sparker built in - also pretty cool and works well.
I got the firesteel mostly because I subscribe to the "at least 3 ways to make fire" rule. I usually overdo that one.
Here's a tip for anyone that is not satisfied with the spark shower from a sparker unit.
Use a piece of old hacksaw blade.
It's way better than a knife because it's very hard. Not strong, but hard, which is what is needed to get a spark shower.