Buy a 15 round pack of both the Remingtons and the Winchesters. Set up some targets at the ranges you will be most like;ly to fire on an animal, and check group placement and size. Go with the one that performs best with your shotgun.
As far as 3 inch slugs go, don't bother with them would be my advice. I have hunted with 2 and 3\4 and 3 inch in the past, and the 2 and 3\4 will kill a deer just as dead. As to the more or less accurate claims, it depends on the shooter and the gun. With my 870, the difference is about a half inch at 50 yards, my wife's 500 is about the same, still well within minute of deer IMHO. Bigger powder charge and more velocity with the 3 inchers are the main difference, not really worth the heavier recoil at 50 yards and under IMO.
Basically, see what the gun likes and go with it.
If I have to explain why I ride, you wouldn't understand. Explaining sex to an alien would be easier than explaining the feeling, one that boils all that is going on in your life down to what really matters each time you are in The Wind. All I can say is, Life is not Life without it.