Leave an amp "on" permanetly

I think there are pros & cons both ways. You say you hear a difference in cold vs warmed up. Do you hear a difference between warmed up vs 24/7? I do a little of both, like with my car. I'm not going to turn the engine off at every red light then back on when it turns green but I will turn it off while I'm eating dinner out. If there's not any difference between warmed up and 24/7, I'd turn it off when there are long periods of non-listening.

my nuforce ref 9 se amps stay on all of the time. no problems

I will say that it is possible for a switch that is turned on and off will eventually give out.

Warming up does matter; but then, after 30min to 1 hour of warming up, things should settle. Leaving it for 24/7 should not be necessary.

Afterall, please do our poor planet a favour. Those mega muscle amps burn a few hundred watts when idling.

I can see how it will not harm components to turn them on and off. But I am curious about the following:

How long does it take the average solid state system to 'warm up' and sound its best?

Will it shorten their life to leave them on 24/7?

And how much electricity is used when they are on but idle?