I was in London last year and went by train, outside of London to their 'Facility" (Hellis). Just a bunch of first class gunsmiths working out of their small shops. I saw the fellow making the locks- like something from 50 years ago. When they say handmade - they just mean - I believe, with very little modern technology. I went to Bosis, outside of Milan. Some would say he is the finest lockmaker in the world. They are wonderful people. He brought out a new lock - magnificent. I am an engineer and have never seen anything quite like it. It was made to his specifications by a Swiss company, machine made. I am sure no one could hand make a lock of this quality BUT at this price would you prefer a gun, perhaps not "perfect" but made on a bench by a craftsman? Just my 2 cents.
As to Purdey Vs H & H locks I feel that Purdey locks are more "alive" than H & H. Again my 2 cents.