You really shouldn't make blanket statements like that. While I'd definitely recommend using existing category 5 wiring if it's available, I'm getting close to 300Mb/s via powerline adapters, so it really comes down to your individual situation. For me it's been more than adequate.

> Powerline Ethernet is not really a good solution either.

Why is that?

It's very finicky about line quality, it likes to be on the same circuit (doesn't cross breakers), and it doesn't live up to the claimed speeds.

As a no longer suffering user of X10 now enjoying ZWave, the issue is usually crossing the out of phase 110 legs (every other full size breaker in the panel is on a different leg).

To cross the phases, the signal has to go to the power pole where the phases originate. X10 has a repeater you can install and sometimes people just install a passive one (a capacitor if I recall.)

In a smaller house, signalling to the panel and back out to circuits on the same leg is more likely to work than crossing the phases.

Thank you for the clarification.