It may be that the sound differences between running the SB wired and non-wired will vary from one situation to the next.
I know that I've had some problems with some sort of RFI coming through my SB2. Some of it may have been generated by the SB2 display. But Vinnie suggested (and Wayne agreed) that some portion of it was likely wireless interference. I don't have a long enough ethernet cable, so I haven't tried to run mine wired yet, but most of the problem seemed to clear up once Wayne treated the unit with some ERS shielding.
Anyway, some people find the display creates some RFI, and some are lucky and don't have that problem. Or, more likely, everyone's display creates some RFI, but it's audible in some systems and not in others. Similarly, I presume that some people will have the wireless interference problem and others won't. It just depends on the environment. But if this is all true, then anyone may find it worthwhile to run the test: if it works better wired then you learn something; if it doesn't make a difference, then you're a lucky sonofa-something-or-other.
Chad