I just bought the $50 Tojiro 210mm white #2 kurouchi. Nice knife, and cheap enough that I thought I would spruce it up a bit (not a disaster if I mess it up). I stuck it in my knife vise (I know you're supposed to put the blade in while sanding the handle, but it works the other way too) and went at it with wet/dry on a sanding block. Here's the knife as it came:
Here it is after some work with 220 (lubed with water and Dawn):
And here it is after 320:
That's where I've stopped for now. It doesn't show in the pics, but the cladding has a nice wavy hammered look that really pops with the kurouchi removed. 1000% better in my opinion.