John,
In an admittedly small sample size (2 packs of each), I’ve found a noticeable difference between Wapsi Sow/Scud Rainbow dubbing and the Orvis version. The Orvis stuff is absolute crap; even after heavily waxing the thread, I couldn't get it to dub on the thread properly; it can work in a dubbing loop but, even then, it’s a pain and much coarser than the Wapsi product. The Wapsi, used in the pics above, worked great, either dubbed on thread or in a loop. Not sure what kind of binder fur Orvis used but it sure didn't compare to the Wapsi, which I think used antron; the amount of shredded mylar seemed to be the same in both products.
Regards,
Scott