Look binko, Boss, H&H, Prudey are for wealthiest most privileged people in the world. This stuff is in the same league as Patek Philippe, Vacheron Constantin,.... Rolls Royce, 10k-15k made to order suit form Milan or Florence,.....finest Italian truffles,..... Only people in right circles know these names.
Few years ago I have actually held and examined one rather closely. It was 20ga O/U made by Purdey i think. I first assumed it was Bosis, Famars or something from Italy. The gun was quite nice (nice wood, SLE, fine english-style small flower engraving largely obscured by CC) and tag had POR on it. Nope, I didn't ask how much.
It was very finely made gun built to fit original buyer and proly patterned to load of choice but it was nothing I couldnt live without. Basically it's "Robb Report" gun. Quite honestly, most people who crave one just think it's much better then it actually is.
