It is more than enough power to drive the Sonus Faber GP's and should sound nice. My Cary SLI-80 drives my GP's with ease in the 40WPC mode. I listen to Rock at moderate to moderately loud volumes in a medium sized listening room.. The CJ signature sound with the Sounus should be nice. Don't get hung up on the WPC channel game. By an amplifier that sounds good to you. Good luck..
Chris
Chris