Purdey's probably gets the lion's share of credit/responsibility for the "London best work gun" fashion. As noted above, after some point the fashion became so entrenched that all gunmakers had to follow. "Swimming upstream" was unprofitable. There is, JMO, an opportunity for to buy bargain quality grade by learning to sort out the "best work" guns of the older, out of fashion and transition guns. Is that flat back SLE an Original Quality grade "A" or is it really a "best work" gun?

DDA