I only have La lune stones. They do have a little more range then Arkansas stones, if you do not factor in surface prepping to change the cutting speed on Arks. I just feel like the slurry creates more problem then the stone can make up for with oil/water etc.An ark is a wonderful finisher...where it really shines is taking an already good edge and making it better. I think if you're using it for maintenance you'd want to be proactive, don't let the edge degrade too much. I have taken edges from "meh" back to great on just the ark, but I feel like I get better results by cleaning up the edge on a synth first. However, if you lap both sides flat and dress one with coarser w/d and the other finer, that could work very well I'd think.
I haven't used the Lune or Black Shadow, for those that have, do these stones have more range than a finishing grade ark?
A coticule can do the same, only better in my opinion.
The feedback with slurry is grate, but as you dilute the stone turns a little glassy and dead.
I get the best results if i use it after a 8-12k, or after a coticule. Then i do only a maximum of 15 strokes. The edge seem to degrade if i stay to long. Not a good sign in my opinion.
That is just my experience.
I would like to try the Black Shadow.