Had a hunting buddy who was quite effective with his A-5. We established that I could get off a second shot with an 870 before he could with his auto.
Neither an 870 nor an A-5 are the fastest cycling examples of their kind. For pumps, probably the Ithaca is the slickest, and my guess is one of the Benellis is the fastest auto currently made.
But it's a non issue in the real world. EITHER style will serve well in trained hands. So, pick one and train,train,train.......