Mossberg 590A1
Mossberg 500 Tactical with tri-rail
Remington 870 Express Tactical
Remington 870 Wilson Combat
Winchester SPX Defender
Not in any order... and for what it's worth:
Last I knew the base gun for the Wilson was ... an 870 Express. If I want a gussied up Express gun I can do that myself, MUCH cheaper.
I personally have no problems with Express guns. I have about a dozen of them, all bought used. I prefer the older, pre-magazine tube dimple guns, because they are basically just roughly finished Wingmasters for the most part. The later ones may have MIM extractors but I have yet to break one of those - and I've run them in (gasp) shotgun classes. An extractor is not a major fix anyway, if an upgrade is desired.
I don't care for anything that calls itself
Tactical. Call me an old phart, I don't care. I am one.
I have three or four Win 1200/1300s. They're good guns basically. Don't know anything about the new imported version though - my first impulse is to be shy of it until it has a track record. Usually when I fail to follow first impulses like that I live to regret it.
A Mossberg 500 is a good house gun. But if I'm going to be outside with a shotgun in the weeds and the wet, I want a design that lends itself to maintaining the tubular magazine. The 500 comes up short in that department. I know, lots of them go for years with little or no attention. But they don't belong to me
.
The 590 cured that magazine design shortcoming, because the military insisted on it. In short there's nothing wrong with the 590A1 (except that it isn't an 870
- that really is a joke). It's available with factory ghost rings - that's what I'd get, if you ever might take it outside. Otherwise a bead will work for inside duties. The only 590 I have has a bead.
So there's the short version. Best advice is, YOU matter more than the gun does, so make yourself the best defensive shotgun shooter possible. The gun will almost certainly do, if YOU will do.