[c-nsp] DiffServ and TE paths are really required to deploy commercial VoIP over a MPLS backbone ?

[jimmi]

Dear members.

There's something I'd like to know from those that truly and successfully 
implement commercial VoIP over a MPLS infrastructure. 

Supporting IP QoS (DiffServ) across the core backbone and/or MPLS traffic-
engineered paths is really required ? 
Consider a hole backbone built with high speed throughput connections, plenty 
of bandwidth availability and no periods of congestion!

I do believe TE tunnels (paths) are necessary for quick recovery when a node 
or link fails, but rather them assuming something I haven't experienced yet 
I'd like to listen from those who really have already successfully deployed 
commercial VoIP.

Best regards.

Jimmi.