I had one of their knives. The bat wing model. It was well made, but too small to be useful. Of the 2 you listed, I'd go with the Work Horse. It's made out of D2 & at a decent hardness (58-60 rc). The Bushcrafter's made out of 4140, of which I'm not familiar with, but I notice they don't list its hardness. Considering the price difference, I think their D2's probably quite a bit better than the other steel.
Hope that helps. However, may I suggest "mykulmorris" knives, who's a knife maker & posts his knives in the knife maker section of this Forum. He's real good at making some nice file knives & I believe he also uses 440C at 60 RC & is starting to work with ATS-34. His prices are very reasonable, too.