Just a reminder - RAID is not a backup. If you are using RAID to protect your data without having a backup solution, your data is at risk. Also, RAID 0 is really not RAID at all and actually increases your chances of data loss.
I currently run 3 NAS devices and have a 4th that I am considering putting to use on my network.
Synology 212J (yes, from 2012) a two bay device that was my first NAS and is currently used as a backup for one volume on my primary NAS. Only runs a few hours a week on an automated power and backup schedule without my intervention. I contains one 10TB drive only so no RAID config here.
QNAP TS-453D 4 drive NAS is my primary data repository. I has 4 6TB drives in a RAID 5 configurations so 18TB of useable storage. I store data backups for myself and DGF, media files for my Windows Media Center server and media files for my Plex server. Also music and photo collections. It's a busy boy. I have a weekly automated backup of volumes to the Synology 212J and a USB3 connected 12TB Wester Digital EasyStore for all my primary backup.
Open Media Vault server - 6 bay SuperMicro Enterprise Level server under the stairs in my basement with four bays filled with 8 TB drives in an array similar to RAID 5 which is use as my secondary backup of my main NAS on a monthly basis. It's a Linux based system which gives me 24TB of useable storage. I also keep a couple of 6 TB drives in separate volumes spinning for test use because why not. This NAS is only powered on sparingly when I need to use it.
Lastly, I have one more 4 bay QNAP TS-453A NAS not in service at the moment. It was my primary NAS for about 4 or 5 years until it failed last fall which is when I bought the TS-453D. I was able to take all four drives from the old NAS and move them to the new one and I was up and running without missing a beat. I have since found out my NAS failure was a known issue with the Intel processor chip it uses and by simply soldering a 100 ohm resister in place it resolved the issue. Now I have another NAS to deploy.
My primary NAS uses one of my 4 CyberPower UPS boxes shared with my router, 2 switches, network controller, AT&T Fiber Modem and a Wyse 5060 thin client running Home Assistant.
The above is tip of iceberg due to too long in IT industry. I need a 12 step program.
