Thus far, the most wicked cutting edges I have obtained have been with kitchen lasers made in one of the Blue or White "paper" steels. With White #2, I find that whether I stop at 600 grit waterstones on the EP or go all the way up to 3000 polishing tape, the edge is just wickedly aggressive and it cuts virtually everything with ease and very cleanly. The edge itself being paper thin helps. I imagine reprofiling a SuperBlue Spyderco with a FFG to a super thin angle would also yield an edge that will cut damned near anything cleanly.
I've found that with my folding knives, thus far M390 gives me the most serious edge. Part of that is because I am down to something like a 13 degree angle, which I don't do with most of my steels but have been doing it with M390 because it holds the scary sharp for prolonged periods even on an edge that thin. Another part is that, to my understanding, M390 is an excellent polishing steel and really benefits from polishing tape, steeling, stropping, etc. in which that final stupid sharp is reached (and held for a long time).
I've found that with my folding knives, thus far M390 gives me the most serious edge. Part of that is because I am down to something like a 13 degree angle, which I don't do with most of my steels but have been doing it with M390 because it holds the scary sharp for prolonged periods even on an edge that thin. Another part is that, to my understanding, M390 is an excellent polishing steel and really benefits from polishing tape, steeling, stropping, etc. in which that final stupid sharp is reached (and held for a long time).
) part time sharpening business, was a straight blade S30v, using the Paper Wheels. It took all of 3 minutes from start to finish to get it scary sharp. It was dull, but not needing re profiling when I started. It was a real pleasure to work with. The stubbornest metal I have worked with is Buck's 420HC. It will get very sharp, but it takes me longer to get a scary sharp edge that I am satisfied with than most other steels I have worked with. Just my experience and YMMV.