Hi George,
In this field I have a little experience. My recommendation, as far a defense, is to stay with the 870 and 590. Neither the extractor nor the quality of the barrels of the 1300 have ever satisfied me.
You can not go wrong with an 870, very smooth system and great accuracy, and a 590 will offer you a very good trigger and a drilled box which will allowed you to install different kind o sights.
Also think in two accessories for your defensive shotgun, a Surefire forearm tactical light and ghost rings. Other stuff is just adding to much weigh, at least form my stand point.
Hope this helps.