I use Rumpf Extra Select Craft Fur. Probably the same as Hareline Extra Select. Could it be the same as craft store fur? Could be.
Like John said, the material does mat up when you catch a fish, but run your fingers/fingernail through it a few times and its good to go. I don't know why, but the stuff just catches fish! Bass, Catfish, Crappies...they all love the stuff.
Here's a bass on a Firetiger-colored craft fur baitfish pattern:


The fly looks like this:


Here's a 19" bass on a chartreuse version (it looks really small down there!):


Catfish like the shad-colored versions:




like this: