I put my main workstation (Win 7/64/Ultimate) in standby instead of shutting it down every day, and it usually "lasts" for at least one month before I need to reboot it, usually for a problem with my watercooling pump very occasionally not starting upon resume (which I talked about in another thread.) So, it's rather stable.
But of course a Linux box is unbeatable for "uptime". I have Linux both on a laptop and on a small workstation box, and if I reboot them, it's for a kernel update. Since I'm on a rolling release distribution, those happen on a regular basis, but that's up to *me*. And, I have built a NAS years ago, running CentOS, and it's on 24/7, updates requiring rebooting are pretty rare on this. Typical uptime is one year or so (rebooting due to either an update, or unexpected power loss with the UPS failing, which has happened.
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