On both my road bike and touring bike, I use a Velocity Synergy on the front and a Synergy O/C on the rear.
I am a firm believer in O/C rims at the rear.
With a Campy hub the NDS spoke tension would be only 44% of DS on a symmetrical rim.
With an O/C rim, the NDS spoke tension is 66% of DS.

My only annoyance with Velocity rims is *finding* the model/finish/spoke-count I need.
The best source I have found for timely delivery is: http://www.peterwhitecycles.com/velocity.asp