is CEPH stable for environment production critical?

Hello people

I had read this link:
http://pve.proxmox.com/wiki/Ceph_Server

But as on this link say that is as technology preview, i think by the moment i will test ceph running independently to the PVE Nodes

In this terms:
1- I want to know what so stable is CEPH for use in environment production critical?
2- Can i run BB.DD. in the KVM VMs without problems of perfomance by access to disk? (always thinking to use a single NIC 10 Gb. ethernet or dual 10 Gb. ethernet over LACP 802.3ad, both options are for use exclusive of CEPH network communication)

Please, I welcome your comments, especially the negative part of CEPH

Best regards