I have for many years used gluster because..well. 3 nodes.. and so long as I can pull a drive out.. I can get my data.. and with three copies.. I have much higher chance of getting it.
Downsides to gluster: Slower (its my home..meh... and I have SSD to avoid MTBF issues ) and with VDO.. and thin provisioning.. not had issue.
BUT.... gluster seems to be falling out of favor. Especially as I move towards OCP.
So.. CEPH. I have one SSD in each of the three servers. so I have some space to play.
I googled around.. and find no clean deployment notes and guides on CEPH + oVirt.