The Spencer 42 is essentially an enlarged Spencer 35. If you compare their numbers on Sail Calculator Pro v3.53 - 2000+ boats
you'll find they are very close. These both predate the Valiant designs. The reason I put the Southern Cross and the Sabre farther down is that they can't all be first.
The only boat on the list I am not exited about is the Bayfield, a design I have never liked the looks of, both above the water (bowsprit with trailboards) and below the water (keel a bit long).