The Musashi MR21 Thumb Swivel is a wide stance hair cutting shear. The MR3 on the other hand is a narrow stance which some feel is easier to “Palm.”
Either the MR3, MR21 or MR23 will provide the relief from the tension and stress you have when cutting hair for hours on end. Do yourself a favor and consider a thumb swivel today. It takes a little time to get accustomed to using a thumb swivel, but once you do, you will never go back.