@wil
Things have changed with the launch of the new USB card.
When using a copper cable to connect to your network make sure it has no shield connecting the preceding switch or router chassis/ground. To verify this I recommend to use a cheap standard cat5 or cat6 network cable (easily identifiable by its plastic / non conductive rj45 plugs), and compare to whatever else you are using.
Fiber and copper still sound different, still respectively more analytical versus warmer. Fiber does indeed benefit more from setting up a VLAN then copper, it is more sensitive to network traffic which can be reduced by this mechanism. We do however not provide support on connectivity issues stemming from doing that.
My personal preference right now is a standard copper cat5 cable which I feel sounds most natural, in my system, your preference may very well be different.