Been using it 20+ yrs, never failed me yet.
Best on the market
I use the color preserver to stick the thread wraps together so they don’t blow up from a bump or loosening of the binding wraps. I apply it to the each thread wrap as it is tied, then blot it, not rub it, with a paper towel til no white is seen. This keeps the wraps from unwinding.
I was naive to think maybe it would not darken the yellow thread that I was using but it did. Lesson learned.