@in1voice , regarding the ER's A and B side, the Uptone guys state that the full benefit is only derived from an input on the A side and the main component receiving the B side's output. The internal "moat" isolates any noise between the two sides.
They additionally state that two components connected to the A-side will benefit from some degree of mutual isolation, though not as much as A-B.
That said, myself and others have seen benefit in the B side by improving the quality of the A side's input (hence my use of fiber). So I guess there are no absolutes here.
Personally, I'm not that fussy about the quality of my TV's ethernet signal, so I would always plug my streamer into the B-side.