I turn everything off after each session. I have a PS Audio P15 and part of its design is that it soft starts everything so there isn't the harsh inrush of current that could be damaging. The other reason is that my system was hit by lightening so it is now off and unplugged from the wall when I'm not listening. One strike is all it takes and that is the end of your equipment that you are trying to get extra life on. I also don't need the extra heat and electrical bill with the five amps being on at all times.
Leave it on?
I just listened to Paul McGowan explain that turning SS equipment on and off degrades the capacitors from the tiny power surge and that leaving SS equipment on ALL THE TIME is best. What do you do?