1095 is about the cheapest "real" high carbon steel you can buy. Just check the prices. That doesn't mean that it is bad. With that said, 56 Rc is not a "super secret heat treatment"to me. It is WAY too soft. If you need to leave your steel that soft to make it tough, you are probably using the wrong steel. But I would say the same thing about Randall using 440B at 54Rc. I have seen shop tour video from one these companies where they are heating up the edge of their knives in a forge and quenching dirty ass oil. "Hard to the core", perhaps, but not exactly super secret and certainly not "best methods"in 2017.
54-56 RC would be Randall's 0-1: Their 440B is 56-58 RC from what I know. Also Randall's shop foreman is on the record that some 440B batches bridge into 440C in Carbon content...
Carbon steels are cheaper mainly because they are easier to grind. The fact that they are easier to grind also means they have somewhat lower edge holding than stainless (contrary to what Randall very strangely claims): Overall, Carbon steels are an inferior grade of steel in almost all respects (see Jay Fisher's opinion on this), but they get sold as a good deal because Carbons have a more "manly" and "traditional" image: Consider the association of "Plastics" with shallow urban phoniness, as made fun of in the movie "The Graduate": Stainless in "tough" fixed blade field knives is seen today in a similar light... This stigma of stainless does not apply to folders, because they are accepted as less "tough" and more "urban" in nature to begin with...
Carbons are much easier to sharpen quickly, which does make the average bloke feel more like a master sharpener, which is perfectly fair, but easier grinding does make for a more rapid thickening of the edge geometry if the mistake of Carbon steel is compounded with the mistake of a flat or convex grind, rather than using a more sensible hollow grind that would at least retain the same edge thickness geometry as the fast-wearing Carbon steel wears away...
But it is all about batoning these days...: That is literally all you see when the toughness and capability of a knife is evaluated (something that would have seemed quite incredible 20 years ago), so, in doing this, inferior fine edge holding is not as big an issue, therefore knives that are used as little more than splitting wedges (with a handle attached) do not suffer so visibly from being made in Carbon...
Gaston