the only functionality qemu-kvm-rhev provides which is not in
qemu-kvm on el6/7 is live snapshots.
So this really should work.
The bug indicated by Francesco is specificaly against RHEL 6.6
"
In Red Hat Enterprise Linux 6.6, support was added for libvirt to report whether QEMU is capable of creating snapshots. However, libvirt did not probe for the snapshot capability properly. As a consequence, the snapshot capability of KVM Guest Image in VDSM was reported as unavailable even when it was available, and creating a disk snapshot in some cases failed. With this update, libvirt no longer reports QEMU snapshot capability, and therefore does not cause the described problem.
"
Sven, you want a too simple life (and me too... ;-)