Not really One you use the shavings enough that side gets softer so it is easier to shave. I just get a nice little pile for about 10 seconds, get a spark to hit the pile and it will take off.

I have never had too much trouble, I read some where that a chunk of a hacksaw blade works good but I never tried this.

My son used to play with one of these when he was in the scouts. He would mix dryer lint with his tender then send a good shower of sparks into the blend it always caught quickly.

We were out with the kids last fall on a "survival skills" day and I tried the flint and steel with magnesium for the first time. I had a fit trying to get the magnesium to light but when I just used the flint and steel to shower sparks into the tinder (like hi_tail above) it caught right away. This was in Colorado which is typically dryer than other areas so maybe my luck was due to environmental conditions, not sure I would have succeeded if the tinder was damp.

Practice with it, and keep one in your pack, but get a good torch lighter and only use the Mag and steel for backup. Use modern technology to your advantage. Also keep a small container of cotton balls soaked in petroleum jelly with your fire kit for fire starter. Some other items that may be in your pack make good starter also, duct tape, potato chips, etc...experiment.

i carry a small warding file to file off shavings. its fast and the powder ignites quickly and it also serves as the steel for the flint, serving 2 purposes at once

I carry a product called WetFire by Ultimate Survival Technolagies and use it in combination with thier BlastMatch. 10 seconds and you have a fire that won't go out and burns for several minutes. The slighest spark lights the WetFire, and while it doesn't burn terribly hot, it is plenty to get a real fire going. I once had a stove malfunction and used one "nugget" to melt a quart and a half of snow for drinking water, not boil, but melt.
http://www.ultimatesurvival.com/product_view.cfm?product_line_ID=157

Yes I thought so when I first tried it took me nearly an hour but you get used to it and when you scrape it it gets softer and easier after a couple of tries you will get a fire in five minutes.

try shaving with the knife at a steeper angle and shave off the corners. that helped me out alot. hopes this helps

Try it in a snowstorm with numb fingers that just won't work so well anymore. The magnesium flakes blowing in the wind look very festive. Been there done that! Carry some cotton balls smeared with petroleum jelly. The sparks will make them burst into flame and if you can get some magnesium flakes to cling to the vaseline all the better and they burn all the hotter.