Evidently some people have been offended by a contrary opinion. I expected to get flamed, so no worries. Facts are stubborn things, aren't they? They are always subject to interpretation, but it is hard to show how sandpaper is so expensive compared to waterstones.
Doug, I am sorry if my reply sounded as if I was offended or engaged in flaming you. That was not my intent.
If what someone is doing to sharpen their tools works that is fine. That is why sharpening threads sometimes become chaotic, there are so many right ways to get it done and everyone finds the one(s) that work best for themselves.
Some folks do not like water stones for valid reasons. They are possibly the messiest means of sharpening. The can get worn quicker than other media and need flattening, just not every 15 minutes in my experience.
My stones cost me less than the stones in the list in your post. Still for many folks the pricing of sandpaper sheets may work better for them than the pricing of stones or diamond plates.
jtk
"A pessimist sees the difficulty in every opportunity; an optimist sees the opportunity in every difficulty."
- Sir Winston Churchill (1874-1965)