I get a pretty darned mirrored edge coming of of a 12k Nani. I would say, if your trying to get a good looking edge, forget the pastes at see how far your stones can take it. Under a 30 loupe the stria should be hard to make out coming from San 8k and the 12 should clean those up in 10-15 laps. Forget about "going too far on the stone" and see what happens. Keep in mind though that a pretty bevel and a great shaving edge are not always the same thing(but sometimes they are).