After learning of them through this thread I ended up getting two South Central twin blanks back in ~Apr 2025 through BBB, one 8.25 twin nose (left), one 8.25 twin tail (right), both 14.25 wb. I really enjoyed skating both, and had intended to stock up on a few more but moved away from the east coast before I had a chance to do so conveniently.
In general, the boards feel ever so slightly thicker than BBS/etc., maybe a touch heavier, but didn't really notice after a session or two. Probably helps keep them from sogging out. The ends of their bottom-plies were also slightly less rounded than most other boards I've had, which (optimistically speaking) gives a lil more time pre-razor tail. The twin nose/tail shapes were overall very similar to each other, but tails a little less fully-shaped, slightly shorter, and slightly steeper than the noses. Maybe tough to tell on worn-board pics. There really wasn't much adjustment to be had when I switched from one to the other.

