ORIGINAL: SP10
A 10 guage is the way to go for waterfowl if money is no object. I do not think you can find a better gun for waterfowl than the Remington SP-10 Magnumfiring 1 3/4 oz. of WingmasterHD shot in #2 for ducks and BB for goose.
just like a .510 caliber bullet is the best for coyote hunting if money were no object