Here's a few videos I just dug up on the "tube" till then. Fluxcore is very widely used in industial settings, like ship building, oil rigs and so on. Most people don't realize that it is one of the most used forms of wire welding. Flux core gets a bad rap from people that don't understand how it is used.
Here's one from Lincoln....
http://www.youtube.com/watch?v=C06aWgJByG0
And esnob
http://www.youtube.com/watch?v=_9bWgMRf9KA
Watch how clean it is and how the flux just falls off....lots of heat though and mostly used on thicker metal....