There was a time when owning a water stone as coarse as 120 grit wouldn't even enter my mind. I couldn't have imagined finding a use for one. That was due to ignorance on my part and even if I did have access to a 120 grit stone at that time I wouldn't have been skilled enough or have the knowledge to get what I could from it.
That was ten years go and things have changed.
I now own the Shapton Glass 120 and Shapton Pro 120.
For the person who sharpens his/her own knives, these stones would likely not be necessary and if you do sharpen your own knives, kudos to you, not many people do that.
For me however, a man who sharpens other peoples knives daily, these are now quite often the first stones I pick up. I like them both the same actually and I got the Glass from Fendrihans.ca and the Shapton Pro 120 off of Amazon.
Why do I like them so much?
They do a superb job of setting the bevels and forming a burr rapidly with moderate pressure. I often follow up with an 800 grit Naniwa Professional stone and the results have really been quite good and I have become quite reliant on these stones. Some would say that they are to coarse and you will remove to much metal needlessly and therefore reduce the life of a knife. If one were to use to much pressure, yes, but that is true with any coarse stone. The bottom line for me is that the fatigued metal has to come off. Why not use a stone that is extremely effective at doing that and one that sets the stage for sharpening success. I have tested these stones on about 200 knives so far and I think they are fantastic.
Again, not something the average sharpener may need if you own a 500 grit stone for example but for repairs, thinning and sharpening very dull knives, they excel.
All the best and thank you so much for being here.