I've used this coarse diamond recrowning file for a good amount of time now, and it's a great help, when I have to recrown and remove a lot of material, in order to reestablish the fret crown.
I own the fine diamond recrowning file as well, and these go well as a pair!

A tip:
Make sure to clean the file, after every few frets, in order to remove accumulated particles. It will make the file last longer.

Excellent tools, high quality and accuracy!