Waterstones for super steels as well as a comment or 2 on diamonds.

[Ankerson]

10v is some serious steel, I've scratched it with other stones but it's only truly sharpened on diamonds. My Shapton Glass stones seem to do a little bit but leave me with an edge lacking a lot of sharpness. IMO, they are not up to be task.

That said, 10v is the only steel that I can't seem to sharpen on my Shaptons, the combination of extreme alloy content and high hardness seems almost stressful to the stones. I find it odd the 10v is so troublesome yet my S110V Native sharpens like butter on the SG stones.

My K2 gets sharpened on a Coarse DMT then stropped on 1 micron CBN. It seems to hold its edge forever unless you get into some serious work. I use my knives often but still have only taken my K2 to the stones a handful of times, stropping seems to keep it maintained for a solid month or two before I feel the need to refresh it on the diamond plate. By comparison, I'm usually visiting the stones 1 or 2 times a week for most other steels.

The biggest deciding factor in using diamond or waterstone is IMO the quality of the heat treatment. If the steel is brought to optimal hardness and the protocol of the heat treatment was strictly controlled then the formation of carbides and distribution of alloys elements is simply much better. As an example: S30V is one steel that seems incredibly difficult for knife makers to HT, there never seems to be two alike HT even from the same maker. I've sharpened some S30V on King waterstones while others have gone seemingly unphased with that same feel on diamond plates that the 10v yields.

I let the steel guide the way for the most part, I can usually gain enough feedback from the stones in a few passes to know what's going to work.

Spyderco put a nice HT on 10V in the K2, it's VERY hard so I can see why.

My SIC Congress Mold Masters cut it like butter however.