Settle your loudspeakers first, then consider what to do with your amplification. If you settle on some higher efficency speakers then you frankly don't need gobs of amplifier power.
Regarding the BC 1000, i had some Ref II's driving difficult planar speakers and they work a treat. Would Pass Lab's also have worked? Sure, but the X350.5 is not exactly inexpensive, neither is it light, nor is compact and cheap to run.
Regarding the BC 1000, i had some Ref II's driving difficult planar speakers and they work a treat. Would Pass Lab's also have worked? Sure, but the X350.5 is not exactly inexpensive, neither is it light, nor is compact and cheap to run.