Heiji carbon gets the edge I like the fastest. TF both steels can feel harder and give less feedback in sharpening and in use. In use it's like I push down into food and then suddenly it penetrates. Heiji is a bit more continuous and I need to press less hard somehow, so it "feels" sharper that way, which is why I like it.
Narutaki suita is my favorite, so I've been using it the most. I have some super duper nakayama kiita (medium-hard and really fine but fastish cutting) and I don't really like them. I also have super hard fine okudo asagi type stuff and shobudani, and they don't really matter much. I would use them for razors, but controlling them for knives is kind of a waste of time, especially for the large bevel. When I mean waste of time, I mean go ahead and buy it if you really want, but I did and I don't like to use them. Choosing a knife and sharpening techniques mattered more, in that order.
In terms of hardness and fineness, it seems like the narutaki is a tad harder than the ohira renge around here, and a tad finer. Just preferences.
I like Heiji carbon > heiji semi > tf denka > tf white, but really, they are more different steels. . . they sharpen and get different kinds of sharp. If you want the most wicked "I don't like you and I never liked you" kind of sharp, the TF denka does that, because after the initial infinitesmally small hesitation, it rips right through food. But I like the Heiji flavor of sharp.
In terms of of polish . . . you can reduce frition substaintially if you polish with a specific polishing stone that don't tend to necessarily give the best edge, but I haven't bought stones for polishing, strictly. If you have hard stone, yeah I guess you can use it to burnish right before the very edge to reduce friction there, then add a real edge.
Edge parallel strokes tend to give less friction for the final edge, so you can do that, too, if you want, but they can have a tad less bite than edge leading and then edge trailing, respectively, in my own practice.
I mean . . . it wasn't a cheap narutaki suita though, so there's that. But really, I don't know. I used the cheaper hideriyama at Japanese Knife Imports and they were muddier than what I like, but I feel I could do well with them too. The muddier stones give a rounded and lower grit edge as default, and I like crisper bevels, so if that's what you're looking for, you can go to the harder end of stones, just not razor hard. Tool hard is the very practical limit, you just have to still have to kind of baby the edge though, and touch ups would require going to a lower grit and then the tool stone if you make it too dull. Not practical for most people; if this was more of a working knife I would get a medium-hard jnat more in the ohira range of things.
Anyway back the khao men -- I think if you get a jnat equivalent of it, it would be great. I think that jnats generally refine down more, even by feeling the grit between my fingers. Maybe choose one just a tad harder, and that would be great. But I think softer stones are more friendly to use cause they cut a lot faster, and if they get too muddy, just wash off the mud and sharpen slowly to approximate what I've been saying with the harder stones.
If you have specific questions you can directly message me as I think I'm getting off topic from khao men.
