I see some fairly interesting prices for refurbished drives on Amazon, 35~40% cheaper than new. Example here: 16TB Seagate Exos X18 Refurbished at 166€ and New at 260€.
I am considering this option for my home NAS, running with BTRFS RAID10, plus important files are backed-up to a cloud storage, but not my media collection.
In your opinion, how risky is it to use refurbished drives ? Do you have to good or bad experience doing so ?
Just bear in mind that nothing involved in “refurbishing” a drive removes the wear it has already experienced. That may or may not matter to you. The mean time between failures for a particular model is a meaningful statistic, but it doesn’t tell you too much about any individual drive. You may get lucky or unlucky with the lifespan.
If you check and monitor your drives, as various people have recommended here, you are less likely to be surprised by a failure. If you keep them backed up you won’t be out anything more than the replacement cost of the drive when it does happen.