I almost never powered off my Dell XPS R 450 for ten years; laziness and the theory of avoiding powerup/powerdown stress on connections. It lasted ten years. I replaced one of the two HDs once. I got rid of it for noise and not worth upgrading it to modern capabilities, and the ginormously large and heavy CRT monitor finally gave out.

I use my laptop as a desktop replacement (see above). I rarely power it down, although Ubuntu boots pretty quick.