I have a couple of them as well (are you getting the idea that I have a obsession for sharp knives?) but use them more for emergency sharpening or "recovery" missions. They hog off a lot of material and after a few uses they begin to create a wavy pattern on the blade. They are effective in getting out nicks rather quickly.
I would not use them on my better/best blades.
"A pessimist sees the difficulty in every opportunity, an optimist sees the opportunity in every difficulty” ---Sir Winston Churchill
"Political extremism involves two prime ingredients: an excessively simple diagnosis of the world's ills, and a conviction that there are identifiable villains back of it all." ---John W. Gardner
“You can’t go back and change the beginning, but you can start where you are and change the ending.” ---C. S. Lewis