@TheNorthernLight Thanks for pointing that out, that totally makes sense, I should have realized to look it up that way. I guess I just think of XCP-ng as its own product so much that I forget it's based on Xen even though I know that.
Different use cases: Ceph is better with more hosts (at least 6 or 7 minimum) while XOSTOR is better between 3 to 7/8.
We might have better Ceph support in the future for large clusters.