First a quick recap of my past data losses. I have had 8 drive failures in the last decade. After the first one that caused painful data loss (even the recovery company couldn't retrieve anything) I bgan buying HD's in pairs with RAID controllers mirroring them. This has saved me many times.
I decided some years ago to buy a NAS with some serious storage to hold my music (lossless compression). I bought a Synology CubeStation and 3 500GB seagate drives and set up in RAID 5. This worried me ever since because sometimes the failures are controller failures not drive failures.
A couple of months ago I started to hear fan noise from the Synology and knew it was time to replace it. It took a while (and some additional hardware failures) for that to reach the top of my list. But I finally ordered a new RAID device.
One of the best things about the Synology was the constant updates and improvements. They took the NVidia/Apple model and kept similar software for all their devices so my old device kept getting addition features, bug fixes and even a couple of complete UI redesigns while I had it.
I decided to try one of those just before the new device arrived. The UI warned me to upload the file to the Synology a different way, but I decided to go for it. The update indeed failed, then the UI stopped responding and then the device started flashing an orange light. It was inaccessible.
I opened a support ticket and they told me to go through the normal install process from a PC connected by ethernet. I balked at this because I did not want to lose data. However, I tried it and it failed. Then I unplugged all the drives and tried again. it failed. Then I connected all the drives and tried again (at their prompting).
Each time I ran the install it listed the steps like 'format system partition' and 'format data partition' - very scary to me. But the last time I tried it went all the way through and when it got to the 'format data partition' step it skipped it! When it all came back it had my data intact. I am quite impressed and very thankful!