The Beesley (Purdey) SxS action is an assisted opening design. That means it uses the springs to add downward pressure to the barrels to make the gun faster to open. The payback is on closing the action, which is correspondingly harder (resetting the spring). The old joke about the Beesley went that an American visiting the Purdey shop once commented about how difficult it seemed to close the action. The salesman sniffed, looked down his nose and replied "most of our clients do not close their own guns." Their is some truth to that. The ultimate guns to take on a driven partridge shoot would be a matched pair of Purdeys or perhaps Holland & Holland Royals. Indeed, the shooter hands the fired gun to his loader while taking the newly loaded one of the pair to fire. Seeing people practiced at this sort of shooting is a bit of a marvel.
That closing issue could, to my mind, be a real handicap in close quarters with a double rifle. It is hot, you are sweating buckets, you have to reload, and that buff is coming from right there. I personally think the Rigby Bissell Rising Bite action is the finest design ever created for a double rifle. Brute strong, elegant, and smooth as silk to manipulate. Rigby is beginning to produce the first new production rising bites in eighty years. Finding one from the golden age before WWII is difficult and prices reflect their rarity.