I constantly watch auctions for information on guns, prices, and makers. It is not unusual to encounter a Scott gun, but it is unusual to encounter a Premiere. Flip side - it is not unusual to encounter a Purdey, but it is unusual to encounter graded sidelocks and boxlocks.

I'm not aware of a formal study, but it sure would be interesting data. The archives of auction house catalogues should make it entirely possible, too.