All the experts I have talked to say don't go to a 12k until you feel you have gotten as much as you can from a 4/8k combo. After a year of straight shaving I embarked on learning to hone from bevel to shave ready on a King 1k for bevel setting and the Norton 4/8k combo. After running the same razor three times thru them and a second one time I finally started getting a decent, if not a little harsh shave after the 8k. When I can get a smooth shave from the 8k I'll think of investing in a 12 or 20k for extra smoothness. Close id the name of the game, smooth is an extra in my book.