Pro and cons of running power amp in 240 V

I was wondering if there is any advantages of running power amp on dedicated 20A , 240V circut why not on 30A ,120V. My power amp can be switched in either voltages .
Solo, there are several advantages. An amp that requires the current, gets it. Two phase is balanced and so is much quieter. I have several Krell amps I had built this way. Are you sure your switch options are both 60hz? I doubt it.