H&H has sold well over 100,000 guns. Many of them were of less than best (OQ1) guns. Purdey's have made/sold some 30,000 guns. Most were best guns. Boss has made some 7,000/10,000, all bests, and Woodward made some 4,000-7,000 guns, most bests. By sheer volume there are many more H&H's and Purdey's, so it is no surprise they are better known. Boss and Woodward tended to be generally lesser known, but not lesser respected by those who paid best gun money for their shootin' iron. Remember, even really obscure makers supplied a few best guns. All best guns cost within, say, 25% of one another.
In the 1880's - 1930's when the guns we chase after were in their hayday, there were many names in contention for lead dog. Only Boss, H&H, and Purdey are CIB at BV1. Of others in contention, only Woodward guns atained BV1. Scott is now at BV3 and Grant is at BV2, for example.
I track gun values by auction results, many per year. So, I think they are a reflection of the market.