Mossberg or Remington?   Um…..   both?    :D  I'll be focusing on the 590A1 in this review however.   I've had several over the years including the 18.5'' model which is probably my favorite due to the balance of it and the availability of 1 & 2 shot extensions.    Here's what I've found over the years with my 590A1s:


Pros:
-Extremely reliable.   So long as the shooter does his/her part and doesn't short stroke the gun there's an very high probability that the gun will go bang when you want it to.  No gun is infallible but this one's about as close as it gets.
-Tons of different factory options out there.   Different stocks, sights, finishes, ect…. can be had from the factory.
-Dual extractors.
-The 590s give you the ability to add mag tube extensions.
-The safety location is equally ergonomic for lefties and righties.
-Parkerized finish.
-Heavier barrel vs. the 500s.
-The shell lifter stays up when loading it.
-Metal trigger guard.


Cons:
-Relatively expensive compared to other pump guns.
-Some folks will consider the aluminum receiver to be a con for the gun (I don't think it matters either way as the lockup is still steel on steel).

All in all the 590A1 is as good as any pump shotgun out there and better than many.   It's seen military/LEO/competition use for many years and continues to prove itself time and time again.   Here's a video with some shooting and a discussion of the pros/cons/features of the shotgun:

I got mine for $300 OTD at a Pawn Shop. They thought it was a 500, I saw where it was clearly marked 590A1 on the receiver, and felt no qualms about offering them less than the tag price

Just picked one up myself about two months ago.  I bought the 18.5" bbl 590A1 w/ GRS for $410.00 from my LGS. I went and added a S&J Hardware +2 extension to it and a SF light in a CDM Gear light mount. I could not be happier w/ the  590 especially being left handed.

The 590a1 is a great weapon. I only owned the 20" model but it was my favorite among all my shotguns at the time. It is a freaking tank.

Do want.

Mine has been great, just the recent trigger issue but that has been resolved.

It's everything I ever wanted on a combat shotgun.

I don't have the A1 Model, mine is a 590, BUT, it DOES HAVE the Mossberg, Aluminum Trigger Group and Safety.  And I'm currently next in line to pick up a 590A1 Heavy-Walled Barrel with Ghost Ring Front Sight.
So it will be a 590A1 in every way except the engraving on the left side of the receiver.

I bought this 590 "Used" at my LGS, and will say that I got it in "Like New Condition", for $325 OTD (with the Aluminum TG & Safety).  This shotgun has performed flawlessly since getting it.  The only things that I've
added to it are a GG&G SS Follower, Military 1.25" Web Sling, Blackhawk Nylon Butt Stock Shell Sleeve, and a set of Uncle Mike's 1.25" QD Sling Swivels'.

It's a Great workhorse of a shotgun.  Has taken everything we've fed it with absolutely no problems at all.
If someone, anyone, would have told me that this shotgun would have performed like this before I got it, I would not have believed them !!!
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