It works real well!!!

Remember, its not for sharpening your lawnmower blades. For keeping an edge on a knife it will last for a good long time.

Be careful of too much flex while sharpening though. Some folks will glue the sandpaper to tile or glass to provide a hard flat surface.

Of course the other option is to glue it to something quite soft - like a mouse pad - and go the convex edge route.