Documentation is very good, but I would have it organized somewhat differently. That's basically what makes this a 9/10 instead of 10/10, for me.
I guess it's like CentOS with the newer Fedora kernel (good approach for a btrfs-based OS, which benefits from newer kernels, and as a heavy Fedora user, I see no problem with the approach).
Simple one-click docker container deployments. Dead simple SAMBA. Once you understand just a few things highlighted nicely in their documentation, you'll find it's remarkably easy and intuitive to navigate. The dashboard is brilliant.
I am *really* enjoying this OS, and I've run FreeNAS, OpenMediaVault, and other popular NAS-type OSes. Not sure a plex deployment could be any simpler and yet so rubust (btrfs).
I don't see myself changing anytime soon. Even bought the Rockstor shirt from their shop today to show some love!