Wow, very nicely done write up - I am preparing 4 gauge amp kit review of popular entry level kits and your data is impressive. I have to point out one thing though and your data proves - Cadence is not OFC, its CCA. They are lying blatantly to their customers or at the very least, doing everything they can to mislead them. Look at the weights of the Raptor and Cadence and KnuKonceptz KCA (Sound Quest maybe mixing CCA and OFC to cut costs too given the weights posted) These are all much lighter then known copper cables. Stinger is even a little light, but they have been down sizing their product for awhile now.
Do you have any good close ups of the Cadence or Raptor? If the inner part of the strand is silvery, then its Aluminum base. The KCA is copper on the outside, AL on the inside so it will have a copper look, but silvery on a flush cut surface. The Kolossus is the exact opposite, copper on the inside, tin on the outside.
Anyways, keep up the good work!