Hey!
Have been using my PS Audio P600 since 2002 I think, powering my whole system including my SET amps... one at a time of course. It can get pretty hot in summer time here in NYC with my SET amp and P600.
I think the P600 main power transformer is always connected to the power to power the touch sensitive on/off power switch, I noticed the chassis is warm even when is off.
Anyway, I unplug the P600 after every time I finish listening to music and plug it back in when I'm listening to music again.
Buddy