I have a Pro Digital passive 7-pin cable and never had a problem with Inbox > D8, although, you are correct, I have heard of others having problems with other manufacturers / vendors passive 7-pin cables. Also, yes, the Core Sound 7-pins are utter pieces of shite.
I don't trust Core Sound's "press releases" worth a damn. It is an intriguing idea, but at this stage, it is just that: an idea. Len is a pleasure to do business with, but these are not status or progress updates, they are just spec sheets or "white papers." If I had a website, I could post anything I wanted on it as well.
I had two Sony 7-pin to optical cables and they both broke. One within five shows and the other before I even got a chance to use it. They are the single biggest pieces of garbage floating around in this hobby. The cable part is simply too thin to withstand any type of field use. I have an Audioquest optical cable that is about 10 times the thickness of the Sony for home audio use and it works like a dream.
Also, I always use the bass rolloff with my CSBs when recording any kind of amplified music. It really helps to eliminate some of the low frequency sounds that would otherwise be distorted by the mics' inability to accurately capture these sounds. It really doesn't do a whole lot for the boominess of these mics, though. I am not an engineer, but I suspect that you can only do so much to modify the mic capsules that Core Sounds uses. Go with the dpa mics if you want a real upgrade from this type of stealth mic.
I have George Wang's CDs of a Tool show from Charlotte, NC in 2001 and it is muddy as all hell. Almost unlistenable. He was using Neumann KM140 > Sonosax > D100 and the bass is unreal. It really gives my car subs a total workout! I know it is not his setup, as I have his Tori Amos CDs as well from Charlotte and it sounds simply fantastic.