finally had to replace the drive setup in my faithful old file server for home...
i've been using a HP N40L Microserver (running windows 2008 R2), with four 2TB in RAID5 (installed as to maximise space at that time), as my main repository for over 10 years...
the seagate 2TB drives weren't new when i put them in, but finally one of them gave up the ghost...
ended up buying two new WD Red 6TB drives, to run in a mirror config (trying to avoid RAID5 from now on), as a replacement for these drives.
our space requirements have lessened now that we have a plethora of streaming apps at our disposal, so haven't needed to acquire and store as many movies and TV shows, as required...
luckily, i have Bird's old QNAP NAS running as my backup and the transition was painless, apart from the file copy...
should give me a few more years of service... i estimate an average up-time over those 10 years as over 95%...