In my case, since fatwood is not readily available from nature and I have to buy it, I prefer the coglan firesticks. Basically the same kindling bit as DotD's emergency starter without the match. I actually prefer the coglan fire sticks to fatwood just because it is so easy to scrap a fine powder with the knife edge that is readily lit with the fire steel. On fatwood its not that bad to do, but it can be finicky, more so then the coglan firesticks.
This is the kit I carry with me everywhere for firestarting. From left to right:
Petroleum coated cotton balls, Coghlan firesticks with starter, Coghlan Fatwood,
Magnesium, and Bic lighter