Tools4Boards has just put out their second generation of Hone Ski and Snowboard Diamond Files & Duo Hone Diamond files. With a choice of two diamond grits, one on each side, the Tools4Boards Hone Duos are a unique option for ski & snowboard edge tuning. There is a very nice feel and feedback from the rigid cast aluminum backs. This is a sweet edge tuning option. Hone Ski and Snowboard Edges Sharp & Smooth with Diamond Stones is better than using metal files for routine maintenance. Files remove too much material, and are less forgiving than diamond files (aka diamond stones). Diamonds can be used in either direction. The progression from coarse to finer grits cuts and the polishes the edges to a smooth, sharp, consistent and longer lasting edge than a file will. This, without creating an irregular, short lived, burr sharp edge that files create. This is similar and desirable much like when you hone a knife sharp and smooth.
Another nice option is that the Tools4Boards Hone Diamond Strips can be replaced if and when they wear out. This is also somewhat unique. Instead of tossing out a used up diamond file and purchasing a new one, old strips can be heated and scraped off to make room for lower cost new diamond strips.
Following is a video from Tools4Boards on using the Hone Diamond Files to sharpen and polish edges: