Eric,
I have the Edge Pro Apex. The stones I use to touch up my S30V blades, when they are still in good shape, would be to start with the 320 grit, then a 400. After that, I use a 600 grit, and finish with a 1000 grit.
On some knives, mostly dead animal processing blades, I will take the really high grit tapes, say up to 2000 grit. I have tapes up to 6K, but have never used those. yet.
