The problem with Furutech and many other cables is that it's always stranded wiring. Furutech actually has very thin strands (which are common). It doesn't matter if it's OCC or silver or the most pure copper you can find. Stranded will always have compromises. If you still want a stranded power cable, probably the best is the
Neotech NEP-3001
from VH Audio. However, I would actually recommend getting an Audioquest NRG-4 (which can be had used for very cheap). Music Direct is actually blowing them out for half price:
https://www.musicdirect.com/cables/audioquest-nrg-4-power-cableIt uses all solid-core conductors which are Audioquests Perfect Surface Copper (very close to OCC). It's a 13awg power cord. Then just chop the ends and apply your Futuech plugs.
I disagree that plugs make the most difference. It's a 50/50 impact between the plugs and the actual cable. Although, many people just don't realize how important the plug connector really is.