Luxury did not define a best gun. Nor was plain finish indicative of a lesser grade. The notion seems strange these days of gold inlays and fantasy engraving. Maybe clients were better informed about the essentials of quality back then.
A prewar sidelock confirmed as best by the makers, had a single trigger, right hand stock, left hand opening lever, non ejector because that is how the original buyer ordered it. He found the right to left opening lever more ergonomic than the usual left to right.
In that world you are who you descend from, net worth, associates you keep what you wear and shoot. What changed is where clothing and guns come from they no longer need to go to Saville Row or London makers Milano and Gardone VT boutiques are acceptable alternatives.