For home defense firearms it comes down to a couple things. First and foremost you have to be able to use it easily in the dark, in a highly stressful situation. Some folks are very familiar with a semiauto pistol. A lot aren’t- Is the clip in? Round chambered? Safety off? Wheel guns are much easier to operate for most folks. Pick it up and star yanking the trigger. With shotguns the same thing applies. You must be able to bring it into action hurriedly in the dark. Whatever you choose I’ve heard good things about the mini shot shells and slug shells for home defense. Years ago I was staying at my girlfriend’s house when the back door was kicked in at 3 am. I jumped up and ran down stairs yelling to get the fuck out! I arrived in the kitchen stark naked with nothing in my hands, as the bandits exited a second or to before I got there. Point being, it mostly happens so very very fast, in the dark, while asleep and you simply react. No firearms were in the home, and truthfully I was standing in the kitchen ready for mortal combat before I was really even aware of it. Let alone having the presence of mind to grab a gun, load it, chamber a round, and safety off blah blah blah.

An 870 with a bullpup conversion is pretty handy indoors.

If the weapon breaks, which one will be easier to find replacement parts?

Go with the pump gun.

Don't dry fire the 870, the firing pin will break.
Have a spare.
Scott

I have a Mossberg 500 and it's a perfect home defense shotgun. Over 50 years and 10 million sold. I have it with night sights, and loaded with double 00, slug, double 00, slug. . . .well, you get the picture.

Benelli 1014, what a fun shotgun. A little heavy but so is my model 12 with a 21 inch barrel and Cutts Comp.-Cam

Scott, the firing pins will break on ANY shotguns if dry fired for any length of time, as well as a lot of 22s The 870s, are not inherently weaker than any other.