You know this, some things can be left on all the time, and some things can't. I wouldn't leave any tube gear on all the time unattended, on the other I think solid state could benefit from being powered up for long lengths of time. It could be true that the act of turning SS on and off a lot with the in-rush of current could increase the risk of component failure.
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?