I have been using Ridgid screw feed cutters for a long time. I am getting ready to buy another set (a 15 and 20). I see that they have regular cutters and Heavy Duty cutters. I understand that the HD cutters will cut steel and heavy conduit. I use these cutters for copper 99.9 percent of the time. My question is should i get the HD cutters? I mainly would like to know if they cut copper as clean as the regular cutters.