How does the Chosera 5000 compare with the Norton 8000 as far as grit rating? It seems that the grit rating system is different between the Naniwa and Norton stones but I can't find exact numbers? Would it be feasible to move to a finishing stone such as an Escher after the Chosera 5000 or is that too big of a jump? The 10,000 is a bit out of my reach at the moment. Any input is greatly appreciated!