I was curious about that Kunz, so I ordered a new M&R and the Kunz. Using new unsharpened no.4 Eagle Mirado's out of the same box, I did a one after the other test. There was no comparison. The M&R sheared away cleanly and quickly to a Very sharp point. The Kunz didn't cut as cleanly and wouldn't take it to as sharp of a point because it was not shearing the cut but rather crumbling it away. The Kunz also had to be emptied. The Kunz also is bigger than I want to take up room in a pocket even on my tool belt.
For a pencil sharpener to keep in your pocket or tool belt, I highly recommend the M & R, and the blade can be sharpened without a lot of trouble but it comes decently sharp to start with. The new one did not work quite as well as the older one in my tool belt that has been sharpened a number of times, but there is no need to sharpen it to start with.
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