This is an interesting discussion. The pros and cons between a pump and a SXS seem to have unnecessarily become a point of conjecture, since the disadvantages of either system can be mostly made up for with training. I like the idea of a pump shotgun for defensive purposes, but I don't see how anyone can say that its difficult to load a SXS while under the pressure of stress, but not the magazine of a pump. That doesn't make sense. Anyone who can manage to stuff 5 rounds into the tube of a pump, can certainly get 2 into a SXS. The shooter who has trained to a level of competence can load his gun, whatever it happens to be, while the person who thinks he's armed simply because he has a shotgun standing in the corner, is not competent, and he discovers loading that gun is a complex problem, when he's lost manual dexterity because he's frightened.
Many, perhaps most of us, know that you can drop a round into the open port of a side ejecting pump gun, push the slide forward, and the gun is then loaded, and ready to put into action, if something happens while you're loading the magazine. That's a nice advantage. What happens though, if you drop that round in backwards? If you don't train, tell me it can't happen. If you dump a box of shells on the bed, then in a panic grab shells to load the gun, tell me it can't happen, particularly if your attention is directed towards the threat. It'll take valuable time to first understand the reason the action won't close, then to pull the slide back far enough to clear the round, and finally shake it out. By contrast, a shell won't go into a SXS backwards, your mistake will be immediately realized, and it only takes a moment to fix; you could even simply drop the round, pick up another, and load it. Again, I'm a pump gun fan, but I'm not blind to the advantages of other actions.
A point against the pump gun became apparent in the assessment of the FBI's infamous Miami shootout. If your arm is injured by incoming fire, you might lose the ability to cycle that pump gun effectively; all of a sudden, a SXS looks pretty attractive, as does a semiauto.