I have thought the Weaver units sold pretty well. I have only ever seen one A unit at the O Scale shows in Chicago, Cleveland or Indianapolis. I think I have seen an AB set on the the Bay and maybe another single unit. I expected to see more of them show up at shows than I have seen.
The Weaver one looked really nice in person.
I wasn't contradicting you, just mentioning that the mechanism does not look Weaver gearboxes. But then I have never seen the underside of one.