If you were relying on the name Purdey to establish an individual gun's quality and you encountered one of their graded sidelocks or a boxlock, you would be set up for a royal (wait, that would be in the case of an H&H) hosing. The name is important to market price at a level of about 2 fold. Actual original quality grade and current condition each are worth 20 fold. Sleeving, refinishing, restoration, etc. factor into current condition.