I can't imagine that someone who has a knowledge and an appreciation for high quality guns with historical significance and is a heck of a shot in the field and moor (and on the ring) would be much criticized if he appeared on a shoot with a fairly high quality gun of any maker or origin, as long as the barrels were side by side. Some shooters of extremely high ability may even be excused for appearing with a gun with barrels one above the other. In other words, a shooter of high ability and knowledge about guns of quality may be within the realm of acceptability if he were to appear at a shoot with a well performing boxlock Greener. A poor shot with no credibility would be "undergunned" with a high condition Boss. Just my opinion, because I'm probably not going to get into the conflict. I'll be here at home.