The NAD is plenty of amp for the Dynaudios, and I'd imagine for the ProAcs as well. I owned the Focus 140 with the NAD C325BEE, and the amp wasn't a problem--the Focus 140 is relatively easy to drive. I own the C372 now, and it's considerably better. It won't be a problem.
The Focus 140 is very smooth with a weighty bottom end, and I consider it a perfect rock speaker, though in my experience it lacked a little midrange transparency for acoustic music. I haven't heard the 1SC, but the other ProAcs I've heard have a few treble spikes that make them seem more "detailed" and "exciting" but get tiring. The Focus 140 is a low to no fatigue speaker.
The Focus 140 is very smooth with a weighty bottom end, and I consider it a perfect rock speaker, though in my experience it lacked a little midrange transparency for acoustic music. I haven't heard the 1SC, but the other ProAcs I've heard have a few treble spikes that make them seem more "detailed" and "exciting" but get tiring. The Focus 140 is a low to no fatigue speaker.