When I bought my mill, it came with a WM drag sharpener. Has the 1030 cam. I used 1030 WM for a while, but I've found better and cheaper bands. I like Simonds, but can't get 4 degree, so right now I'm using mostly Kasco 4s and 10s. My sharpener is setup to do the Kasco 10s because Kasco uses the WM 1030 profile. I haven't tried sharpening the Kasco 4s, but I imagine it's only a matter of tipping the rock to 4 degrees instead of 10, and the 1030 cam would probably work for the Kasco 4s. So to answer your question, it's a matter of not enough time. I run a very small sawmill operation as a side business. I do portable jobs, and I harvest my own trees and sell lumber. Between sawing and logging, and the good ole full time job that keeps getting in my way, I just don't want to spend the time sharpening. I've heard great things about the Cats Claw, maybe that would change my mind by decreasing the time to sharpen, not sure. But that's where I'm at. I would love to do what mountainlake does ... buy Simonds 10 deg for less than $14 a pop and resharpen them myself to 4 deg. Right now, my band expense is .04-.06 per bft. When I was sharpening I had it closer to .02.