I've used the two stop collars many times with great success. Yes, I've made fun of the problems folks have had over printing scales and getting them to the right size. Actually, I still think worrying about less than a quarter turn (1/64") is kinda silly. But thought I'd try the stick on vernier because it is such a pretty yellow color:p .
What amazed me when I got the scales was the 8 page, full color instructions that came with them. Imagine that! 8 pages of instructions to stick a scale on the collar.

Now if I ever find a need to raise or lower a table I can read how much in thousandths, millimeters, or fractions of inches. Since the scales fit exactly - those measurements have to be correct - right?
For those of us really interested in that kind of accuracy these scales are the "cats meow"!