Yeah, it does make definitely sense to go to diamond based abrasives (I use 400 and 2000 stones from Practical Sharpening and a small diamond stone from Venev) with high Vanadium steels, simply because vanadium carbides are (considerably) harder than the abrasives in ceramic stones and while one can still use the stones (it will take considerably more time), the resulting edge does not last as long as it does after sharpening with diamond stones/plates. Personally I would not go past CPM M4, Cruwear, S30V, MagnaCut, etc. with non-diamond abrasives. Steels like S90V, S110V, Maxamet, Rex121, k390 or similar, really deliver their full potential only with diamond based abrasives.