polishing is not filing or sanding, did not understand all the reviews on the internet well enough...
-fret ends were sticking out, coming loose at the edges of some of my HB guitars. Finally solved with light hammering the edges down, filing with keyholes the edges that were sticking out on the sides. (wet) sandpaper 1000 for the basics
then finally with this rubber polish the fret ends.
That worked well, take you're time for each fret-end. It leaves just eraser dust instead of steelwool misery . So its not a "magic" tool, but nice for final "shine" treatment. like buffing. Maybe a complete set would allow for more "sanding" but that would be very expensive.
Since i play all my guitars, shining the frets itself is not needed.