I really like the BBW combined with lower grits, in particular shapton glass 320 and shapton glass 500. I get amazing results with this combo. What I dislike about my BBW is that it gives too much polish to the edge. The stone I have that’s the most similar is the arashiyama 6000, so maybe my BBW is rather fine. The vendor claimed that is 5000 grit which I tend to agree. I was quite disappointed until I figured out that the BBW cleans very quickly any burr from coarser stones, so I use it a lot when I go lower in grit. I use the BBW in O2, 26C3, aogami 1, aogami 2 and 1.2419 knifes.
I do agree with previous claims that the BBW is good for kasumi. It’s amazing how easy is to polish with it.
My favorite stone for touch ups and to have a edge with a lasting bite is the Naniwa Pro 3000. I tried the Morihei 4000 and the BBW and neither really works as well. They have their place, but with my knifes and with my technique I can’t extract enough bite from them that would bring a knife with a slippery edge to an edge with bite and that that bite would last a full meal prep. This is more evident in my 26C3 and aogami 2 knifes. The others are different beasts, but still the chosera 3000 is the one that makes them sing the tune I like.