I have been told that powering up an amp puts stress on the components with solid state equipment. I keep my Krell S-300i either on or standby and I never reach around and turn it off completely. Now if I am going to be away for awhile I do turn off and unplug. No real reason just feel better doing it. I am sure a well designed product from Musical Fidelity would be fine to leave on or standby. You may have a slight increase in your electrical bill.