I have used them ever since they came out, I got great blood trails, so I mixed in 160 single bevel custom ground Hills. We never lost a deer with either one and on the average we got more blood on the ground quicker. At first I sharpened them exactly as the instructions on the package stated. I bought a bunch of Grizzly files when Elburgs sold out. The Grizzly file has a round narrow side that can be used like a steel and this leaves the single cut file teeth jutting out with very defined teeth. I still file sharpen, then clean that up with a diamond hone and a leather strap. Then going from back to front with file reversed and at about a two way 45 degree angle on the beveled side of the head I pull a serration. Then finish with a couple of light flat strokes on the flat side and some hair and some air on the beveled side with the rounded narrow side of the file. This has shortened our blood trails and puts even more blood on the ground on average. I have no doubts about shaving sharp, but adding this serration seems to do that little bit more.