Purdey have their own regulators, or at least they did a few years back when I was able to visit their factory.

H & H's old Dominion range were made by W.C Scott, and I have it on good authority that not too long ago in the last century much of their Royal range was outsourced to trade makers when they took more orders than they could satisfy in house, but have no doubt they will deny that!

As to the merits of the W-R droplock, it is the highest refinement of the boxlock concept, which in the original Anson & Deeley pure form began at W-R in the mid 1870s. Check out their latest website for wonderful pictures to drool over.

For a discussion of many of the action features, which is not too technical, look up Hadoke's "Vintage Guns for the Modern Shot" 2007.