I've been using unraid since the late 4 and early 5 days. I've had storage arrays as big as 40TB and now I'm down to a decent 20TB. I've survived 2 simultaneous hard disk failures (thank god for backups), a busted parity drive, cache that has become corrupted, and each time I can say that most of my data has survived. I purchased 2 professional (26 disk) keys from Tom back in the day and this was the best money I ever spent as he has walked me through reviving my array when I thought all was lost. Yes, your purchase comes with support FOR LIFE. No other vendor does that as they all want a damn subscription every year where you pay them for nothing.
UnRAID 6 is awesome. It's on the Xpenology side of useability and feature set. I've got Docker running with multiple containers running Plex, OpenVPN, DuckDNS, UniFi (ubiquiti), and Deluge all running along taking 0 CPU resources on a 4 year old AMD platform. The best part is if I want a different container I click on the search store and the install button and the container is downloaded and installed.
UnRAID just works, it's the Toyota Camry of the Open source storage vendors. It can do MANY things, you can tweak it, install more parts to it, throw any old hard drive you want at it and the damn thing keeps trucking along. I've tried FreeNAS, Xpenology, OpenFiler, Linux with ZFS, and Linux as a storage service. UnRAID is by far the easiest to setup, supports nearly everything that's qualifies as an x86_64 CPU and buttload of controllers for storage. The UI has come a loonngggg way since the Bubba days (old UnRAID users will understand) of tweaking, and the UI is simplified down to make it so damn easy to use. I've talked 3 other people into trying UnRAID after they've messed around with other projects, all said it was vastly easier to use and that's the key.
Would I use it in my home? Absolutely 1000x yes. Would I use it as a backup at a SMB? Yes. Would I use it as a file server at a SMB? Yes. Would I use this in an enterprise solution? Never. I build enterprise solutions, UnRAID is not designed for those rigorous requirements.
Also, if you are on the fence holding out for Dual Parity drives, be real. You don't need it, you won't use it, dual parity is a waste of a disk for 99% of the users out there, and it's one of those "I MUST HAVE THIS!!11!!" feature that people clamor for and never use. I have been pushing for MORE disks instead (current limit is 26 disks) and would rather have a bigger focus on that vs. dual parity. That or to tighten up the cache disk headaches with BTRFS.