First off I would never own a double in .375 caliber or any none rimmed caliber for that matter..but the 375 just conjurs up too much pressure for a double IMO...

Of the ones mention, the only one that I would have would be the Heym but I would suggest a William Douglas or better yet the new Searcy PH, which is what I presently have and I like it really well, other than that I would only have an English gun...I like Jefferys, Army/Navy and a few others in the plain jane figuration.

Now this is only my personal opinnion and a couple of thoes makes I have not even seen, but have talked to folks who have, and whos judgment I respect...