I agree with @sokogear. I use a Plinius pre and amp and my rig is always on unless I go on vacation. I always power everything down then just because of potential lightning storms. My rig has run this way for years. The way I look at it, cooling and re-warming is like bending a piece of metal, eventually it will break. I don't know if there is any validity to that hypothesis but that's what I do.