I use a mirror edge. When carving on woods that are good and hard,the polished edge leaves a polished cut. When doing very small,detailed carvings,like the Lion's head violin neck,I want every cut to be cleanly cut and polished. I haven't posted pictures of my boxwood lute rose(can be seen at George Wilson Guitar Maker),but that,and some of my other carvings are just too small to be sanded,or cleaned up. The surfaces were left as cut.