Have you checked Shapton Pro 2000? does it finish nicer than Bester 2k? Or have you played around with Nagura stone? sometimes some slurry could help polish the knife nicely.
No, did not try it. I got only Shapton pro 5000 in that brand, nice stone but don't use it so much as I prefer going naturals earlier.
I just did the begginning of a test :
Test knife is 185mm petty, bevel is about 12/13mm wide. san mai Mild steel + C130 as usual.
Disclaimer : it's very difficult to get true and honest information during the test, the two sides of the blades are slightly differents and I am working ambidextrious so maybe left hand is not as strong as right hand.
The blade is grinded on my 36 grit whetsone wheel, then I go on 120 grit sand belt to get even & flat before goind to stones.
First fight : JNS 400 (right side) vs Naniwa Pro 400 (left side) : JNS wins, 11 minutes to erase 120 grit scratches and form the bevel right in thickness and geometry. Naniwa pro 400 for the same job took me 20 minutes.
This is going on contrary than my previous test ! I think right side had to be cleaner than left one before the stones. But my feelings tell me JNS wins anyway : harder stone so to me better feedback, very good abrasion (bevel get light kasumi (full of scratches of course)), not as much mud so I am not always cleaning it and it doesn't slowing me down. I had to flattend naniwa at mid period, I didn't with JNS. Naniwa feel more abrasive and soft, but JNS was working really fast and the figures can't be that wrong, it took me nearly two times less with JNS.
Second fight : Bester 2000 (right side) vs Naniwa pro 1000 (left side) : Bester wins with one minute less (9 minutes vs 10 minutes). To my feelings Naniwa was maybe a bit faster because there were more job to do on the left side. Naniwa is really far more softer than Bester which is hard stone. Scratches do look finer with Naniwa than the Bester ones. So they are almost equality but Naniwa is little bit faster and finer scratches vs Bester is doing clear kasumi (like it because you can see easier even on clad if you erase the previous scratches) and is harder (like it for the feedback and for keeping the stone flat on my bevel easily).
Third fight : Natsuya (right) vs Natsuya (left) : just to see if Natsuya can erase the 1000/2000 scratches and how much times it takes with Natsuya to erase Bester vs Naniwa scratches. Natsuya took me 15 minutes to erase all Naniwa 1000 scratches and get nice clean bevel. I try for about 11 minutes to erase Bester scratches with Natsuya and it was not working : I could erase most of it but there were 30% of scratches that were too deep to clean them with Natsuya. I think it could took me about.... 25 maybe 30 minutes if I wished to erase those deeper scratches. So clearly Naniwa 1000 makes shallower scratches than Bester 2000. Now, my final thought about this fight is that I wish my Natsuya could be slightly coarser so I can be really confident at erasing any 1000 scratches coming from Naniwa or Bester. In both case, to get the guaranty that all 1000 scratches (even Naniwa ones) are erased before going finer in grain, I think I would use a stone in between, fore Natsuya, just to be sure scratches are all erased and can be confident to go Natsuya and then whatever stone I want to use without discovering any 1000 grit scratches.
This afternoon (it is about 1:30PM in France) I will make the fight between the different stones I got to erase 1000 grit scratches. I will do the test with Bester scratches on the blade (because I prefer harder stones vs Naniwa 1000) and anyway if I can erase Bester 2000, it means I can erase Naniwa 1000.
Give you some news soon,
Yeah Pro 30k is much more expensive, unless you find a reasonable dealer, it can be close to what glass 30k costs. 
