To date I hardly could get some patina on mine Yoshi SKD core at all, counting onions garlic and tomatoes in preps. I’m not one to wipe down in between or run to wash immediately after.
Naniwa Pro 400 and 800 I can confirm they're quite good stones. The NP400 is not the fastest and I'd feel barenaked without a couple coarser alternatives, but it's also the most undemanding coarse stone I've tried, and it just doesn't dish. Good for mild thinning, maintenance, setting bevels, minor repairs or reprofiling. Leaves a relatively nice kasumi-like finish if you get some mud working for you. The NP800 is a smooth, versatile stone. You could stop many cheap SS right there, deburring and all. Leaves a keener edge than SP1K, with a level of refinement closing on SP2K.
Edit: ah yes I forgot to tell, NP400 can sharpen deburr and be refined to a nice butchery edge level - also a nice one stop option for cheap SS where you want lasting bite. Tremendous starting stone in a full sharpening progression with better steels - feels so smooth, works fast enough.