When hunting driven game I believe a 9,3 would get the game down quicker and allso leave a bether blood trail if wounded. When hunting in Poland for example that is a clear advantage as the search for wounded and shot after game is done quite quickly, compared to similar hunts in Sweden.

As for the 8x57irs I think it perhaps is the most suited double rifle calibre of them all for european sriven hunting. The recoil is very managable for quick and accurate double shots and it has enough power for both moose and large boars.

I dont think you would go much wrong with a 7x65r either, but I would rather use that calibre for stalking and pick a 9,3x74r for driven hunting with a double.