Benefit of shielded ac wire? Any downside?

tantejuut

... I have wired my system from the breaker panel with starquad 12 awg solid core wire direct to my distribution block. And a 10 awg , counter rotating, earth wire ...

Was this wire rated for the purpose and for in-wall use?

THe benefits:
Better rejection of EMI/RFI signals, like from routers, switches etc.
Negatives:
None really, though some claim the sound is duller.  I say it's because you are hearing less noise.

@cleeds . It is standard wire. I just braided it myself. It is a double run, normal wire for in wall use twisted in starquad. Pitch twist about 4 inch. It took a while for 15m. A good foundation for my system. Direct connection to my star wired distribution block, skipping wall outlets & power connectors.  

@ptss:
Run a 10/awg BX- cable solid core conductor from the breaker panel to a metal receptacle box. The metal sheathing on the BX-cable absorbs the (EF)) electric fields emitted by the wires and shunts it to ground. Now from panel to plug is shielded. The upside is low line noise and reduced antenna effect. Downside BX-cable is pricier. Hope that helps. Mike.  

Checking into BX it seems like the sensible option as it also protects from nails, screws and rodents.
I wonder what hi-fi companies that sell high end like Spectral, Pass, Levinson, Goldmund, FM Acoustics, Constellation - advise their clients re home wiring?